diff --git a/trytond/ir/cron.xml b/trytond/ir/cron.xml
index f164ef44a5..893bedb0f0 100644
--- a/trytond/ir/cron.xml
+++ b/trytond/ir/cron.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms. -->
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
 <tryton>
     <data>
         <menuitem name="Scheduler" parent="menu_administration"
@@ -51,7 +52,8 @@
                     <field name="nextcall"/>
                     <label name="doall"/>
                     <field name="doall"/>
-                    <separator string="Action to trigger" colspan="6"/>
+                    <separator string="Action to trigger" colspan="6"
+                        id="action_trigger"/>
                     <label name="model"/>
                     <field name="model"  readonly="1"/>
                     <label name="function"/>
diff --git a/trytond/ir/default.xml b/trytond/ir/default.xml
index 27f74c254c..b4f7abcada 100644
--- a/trytond/ir/default.xml
+++ b/trytond/ir/default.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms. -->
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
 <tryton>
     <data>
         <record model="ir.ui.view" id="default_view_form">
@@ -14,7 +15,7 @@
                     <field name="field"/>
                     <label name="user"/>
                     <field name="user"/>
-                    <group col="2" colspan="6" expand="1">
+                    <group col="2" colspan="6" expand="1" id="value_clause">
                         <separator name="value"/>
                         <separator name="clause"/>
                         <field name="value"/>
diff --git a/trytond/ir/lang.xml b/trytond/ir/lang.xml
index 9a7423f030..bb4614f7d6 100644
--- a/trytond/ir/lang.xml
+++ b/trytond/ir/lang.xml
@@ -69,10 +69,10 @@
                     <field name="direction"/>
                     <label name="translatable"/>
                     <field name="translatable"/>
-                    <separator string="Date Formatting" colspan="6"/>
+                    <separator string="Date Formatting" colspan="6" id="date"/>
                     <label name="date"/>
                     <field name="date"/>
-                    <separator string="Numbers Formatting" colspan="6"/>
+                    <separator string="Numbers Formatting" colspan="6" id="number"/>
                     <label name="grouping"/>
                     <field name="grouping"/>
                     <label name="thousands_sep"/>
diff --git a/trytond/ir/model.xml b/trytond/ir/model.xml
index 7134ec6864..996e3a31e3 100644
--- a/trytond/ir/model.xml
+++ b/trytond/ir/model.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms. -->
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
 <tryton>
     <data>
         <menuitem name="Models" id="menu_models" parent="menu_administration"/>
diff --git a/trytond/ir/module/module.xml b/trytond/ir/module/module.xml
index 5f81589e85..df89074fc8 100644
--- a/trytond/ir/module/module.xml
+++ b/trytond/ir/module/module.xml
@@ -10,7 +10,7 @@
               <![CDATA[
                 <form string="Module">
                     <notebook>
-                        <page string="_Module">
+                        <page string="Module" id="module">
                             <label name="name"/>
                             <field name="name"/>
                             <label name="shortdesc"/>
@@ -26,7 +26,7 @@
                             <newline/>
                             <label name="state"/>
                             <field name="state" readonly="1"/>
-                            <group col="6" colspan="2">
+                            <group col="6" colspan="2" id="button">
                                 <button string="Mark for Installation" name="button_install"
                                     type="object" states="{'invisible': '''state != 'uninstalled' '''}"/>
                                 <button string="Mark for Upgrade" name="button_upgrade"
@@ -41,7 +41,7 @@
                                     type="object" states="{'invisible': '''state != 'to remove' '''}"/>
                             </group>
                         </page>
-                        <page string="_Dependencies" col="1">
+                        <page string="Dependencies" col="1" id="dependencies">
                             <field name="dependencies">
                                 <tree string="Dependencies">
                                     <field name="name"/>
@@ -139,11 +139,11 @@
                 <![CDATA[
                 <form string="Welcome to the module configuration wizard!" col="2">
                     <image name="tryton-dialog-information"/>
-                    <group col="1">
+                    <group col="1" id="labels">
                         <label string="You will be able to configure your installation"
-                            align="0.0"/>
+                            align="0.0" id="configure"/>
                         <label string="depending on the modules you have installed."
-                            align="0.0"/>
+                            align="0.0" id="depending"/>
                     </group>
                 </form>
                 ]]>
@@ -167,13 +167,13 @@
                 <![CDATA[
                 <form string="System Upgrade" col="2">
                     <image name="tryton-dialog-information"/>
-                    <group col="4">
+                    <group col="4" id="labels">
                         <label align="0.0"
                             string="Your system will be upgraded."
-                            colspan="4"/>
+                            colspan="4" id="upgraded"/>
                         <label align="0.0"
                             string="Note that this operation my take a few minutes."
-                            colspan="4"/>
+                            colspan="4" id="operation"/>
                         <separator name="module_info"/>
                         <field name="module_info" colspan="4"/>
                     </group>
@@ -189,7 +189,8 @@
                 <![CDATA[
                 <form string="System upgrade done" col="1">
                     <label align="0.0"
-                        string="The modules have been upgraded / installed !"/>
+                        string="The modules have been upgraded / installed !"
+                        id="modules"/>
                 </form>
                 ]]>
             </field>
diff --git a/trytond/ir/rule.xml b/trytond/ir/rule.xml
index 119ba0a74b..e224b6bfc6 100644
--- a/trytond/ir/rule.xml
+++ b/trytond/ir/rule.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms. -->
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
 <tryton>
     <data>
         <record model="ir.ui.view" id="rule_group_view_form">
@@ -18,9 +19,9 @@
                     <field name="name" colspan="5"/>
                     <field name="rules" colspan="6"/>
                     <label string="The rule is satisfied if at least one test is True"
-                        colspan="6" align="0.0"/>
+                        colspan="6" align="0.0" id="satisfied"/>
                     <label string="If there is no test defined, the rule is always satified if not global"
-                        colspan="6" align="0.0"/>
+                        colspan="6" align="0.0" id="no_test"/>
                 </form>
                 ]]>
             </field>
diff --git a/trytond/ir/sequence.xml b/trytond/ir/sequence.xml
index aa91314b97..2c8e8b9db5 100644
--- a/trytond/ir/sequence.xml
+++ b/trytond/ir/sequence.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms. -->
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
 <tryton>
     <data>
         <menuitem name="Sequences" parent="menu_administration"
@@ -27,13 +28,14 @@
                     <field name="number_increment"/>
                     <label name="number_next"/>
                     <field name="number_next"/>
-                    <separator string="Legend (for prefix, suffix)" colspan="4"/>
-                    <label string="Year:"/>
-                    <label string="${year}" colspan="3" align="0.0"/>
-                    <label string="Month:"/>
-                    <label string="${month}" colspan="3" align="0.0"/>
-                    <label string="Day:"/>
-                    <label string="${day}" colspan="3" align="0.0"/>
+                    <separator string="Legend (for prefix, suffix)" colspan="4"
+                        id="legend"/>
+                    <label string="Year:" id="label_year"/>
+                    <label string="${year}" colspan="3" align="0.0" id="year"/>
+                    <label string="Month:" id="label_month"/>
+                    <label string="${month}" colspan="3" align="0.0" id="month"/>
+                    <label string="Day:" id="label_day"/>
+                    <label string="${day}" colspan="3" align="0.0" id="day"/>
                 </form>
                 ]]>
             </field>
diff --git a/trytond/ir/translation.xml b/trytond/ir/translation.xml
index 7d26e17c4d..2c243f29c1 100644
--- a/trytond/ir/translation.xml
+++ b/trytond/ir/translation.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms. -->
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
 <tryton>
     <data>
         <record model="ir.ui.view" id="translation_view_form">
@@ -20,7 +21,7 @@
                     <field name="lang"/>
                     <label name="module"/>
                     <field name="module"/>
-                    <group col="2" colspan="6" expand="1">
+                    <group col="2" colspan="6" expand="1" id="src_value">
                         <separator name="src"/>
                         <separator name="value"/>
                         <field name="src"/>
@@ -130,7 +131,7 @@
             <field name="arch" type="xml">
                 <![CDATA[
                 <form string="Set Report Translations">
-                    <label string="Synchronize Report Translations?"/>
+                    <label string="Synchronize Report Translations?" id="synchronize"/>
                 </form>
                 ]]>
             </field>
@@ -142,7 +143,7 @@
             <field name="arch" type="xml">
                 <![CDATA[
                 <form string="Set Report Translations">
-                    <label string="Set Translations Succeed!"/>
+                    <label string="Set Translations Succeed!" id="succeed"/>
                 </form>
                 ]]>
             </field>
@@ -164,7 +165,7 @@
             <field name="arch" type="xml">
                 <![CDATA[
                 <form string="Clean Translations">
-                    <label string="Clean Translations?"/>
+                    <label string="Clean Translations?" id="clean"/>
                 </form>
                 ]]>
             </field>
@@ -176,7 +177,7 @@
             <field name="arch" type="xml">
                 <![CDATA[
                 <form string="Clean Translations">
-                    <label string="Clean Translations Succeed!"/>
+                    <label string="Clean Translations Succeed!" id="succeed"/>
                 </form>
                 ]]>
             </field>
diff --git a/trytond/ir/ui/board.rnc b/trytond/ir/ui/board.rnc
index 9bd3d79d56..9e30c02b21 100644
--- a/trytond/ir/ui/board.rnc
+++ b/trytond/ir/ui/board.rnc
@@ -5,7 +5,7 @@ board =
     attlist.board,
     (image
      | separator
-     | labe
+     | label
      | newline
      | notebook
      | group
@@ -26,7 +26,7 @@ attlist.image &= attribute help { text }?
 attlist.image &= attribute states { text }?
 separator = element separator { attlist.separator, empty }
 attlist.separator &= [ a:defaultValue = "" ] attribute string { text }?
-attlist.separator &= attribute name { text }?
+attlist.separator &= ( attribute name { text } | attribute name { text } )
 attlist.separator &= attribute states { text }?
 attlist.separator &=
   [ a:defaultValue = "0.0" ] attribute align { text }?
@@ -39,7 +39,7 @@ attlist.separator &=
 attlist.separator &= attribute help { text }?
 label = element label { attlist.label, empty }
 attlist.label &= [ a:defaultValue = "" ] attribute string { text }?
-attlist.label &= attribute name { text }?
+attlist.label &= ( attribute name { text } | attribute name { text } )
 attlist.label &= attribute states { text }?
 attlist.label &= [ a:defaultValue = "0.0" ] attribute align { text }?
 attlist.label &=
@@ -51,7 +51,7 @@ attlist.label &= [ a:defaultValue = "1" ] attribute xfill { "0" | "1" }?
 attlist.label &= [ a:defaultValue = "1" ] attribute colspan { text }?
 attlist.label &= attribute help { text }?
 newline = element newline { attlist.newline, empty }
-attlist.newline &= empty
+attlist.newline &= attribute id { text }
 notebook = element notebook { attlist.notebook, page* }
 attlist.notebook &=
   attribute tabpos { "up" | "down" | "left" | "right" }?
@@ -61,7 +61,7 @@ page =
     attlist.page,
     (image
      | separator
-     | labe
+     | label
      | newline
      | notebook
      | group
@@ -73,12 +73,13 @@ attlist.page &= attribute angle { text }?
 attlist.page &=
   [ a:defaultValue = "Unknown" ] attribute string { text }?
 attlist.page &= [ a:defaultValue = "4" ] attribute col { text }?
+attlist.page &= ( attribute name { text } | attribute id { text } )
 group =
   element group {
     attlist.group,
     (image
      | separator
-     | labe
+     | label
      | newline
      | notebook
      | group
@@ -93,18 +94,22 @@ attlist.group &=
 attlist.group &= [ a:defaultValue = "1" ] attribute fill { "0" | "1" }?
 attlist.group &= [ a:defaultValue = "1" ] attribute rowspan { text }?
 attlist.group &= [ a:defaultValue = "4" ] attribute col { text }?
-hpaned = element hpaned { attlist.hpaned, child1?, child2? }
-attlist.hpaned &= [ a:defaultValue = "4" ] attribute colspan { text }?
-attlist.hpaned &= attribute position { text }?
-vpaned = element vpaned { attlist.vpaned, child1?, child2? }
-attlist.vpaned &= [ a:defaultValue = "4" ] attribute colspan { text }?
-attlist.vpaned &= attribute position { text }?
+attlist.group &= attribute id { text }
+
+hpaned = element hpaned { attlist.paned, child1?, child2? }
+
+vpaned = element vpaned { attlist.paned, child1?, child2? }
+
+attlist.paned &= [ a:defaultValue = "4" ] attribute colspan { text }?
+attlist.paned &= attribute position { text }?
+attlist.paned &= attribute id { text }
+
 child1 =
   element child1 {
-    attlist.child1,
+    attlist.child,
     (image
      | separator
-     | labe
+     | label
      | newline
      | notebook
      | group
@@ -112,13 +117,13 @@ child1 =
      | vpaned
      | action)*
   }
-attlist.child1 &= empty
+
 child2 =
   element child2 {
-    attlist.child2,
+    attlist.child,
     (image
      | separator
-     | labe
+     | label
      | newline
      | notebook
      | group
@@ -126,20 +131,30 @@ child2 =
      | vpaned
      | action)*
   }
-attlist.child2 &= empty
+
+attlist.child &= attribute id { text }
+
 data = element data { attlist.data, xpath+ }
 attlist.data &= empty
-xpath = element xpath { attlist.xpath, any }
+
+xpath = element xpath { attlist.xpath,
+    (image
+    | separator
+    | label
+    | newline
+    | notebook
+    | group
+    | hpaned
+    | vpaned
+    | action
+    | page
+    | child1
+    | child2)*
+  }
 attlist.xpath &= attribute expr { text }
 attlist.xpath &=
   [ a:defaultValue = "inside" ]
   attribute position { "inside" | "replace" | "after" | "before" }?
 action |= notAllowed
-labe |= notAllowed
+label |= notAllowed
 start = data | board | label
-any =
-  (element * {
-     attribute * { text }*,
-     any
-   }
-   | text)*
diff --git a/trytond/ir/ui/board.rng b/trytond/ir/ui/board.rng
index 8534f60a4d..e4cf28655d 100644
--- a/trytond/ir/ui/board.rng
+++ b/trytond/ir/ui/board.rng
@@ -7,7 +7,7 @@
         <choice>
           <ref name="image"/>
           <ref name="separator"/>
-          <ref name="labe"/>
+          <ref name="label"/>
           <ref name="newline"/>
           <ref name="notebook"/>
           <ref name="group"/>
@@ -84,9 +84,10 @@
     </optional>
   </define>
   <define name="attlist.separator" combine="interleave">
-    <optional>
+    <choice>
       <attribute name="name"/>
-    </optional>
+      <attribute name="name"/>
+    </choice>
   </define>
   <define name="attlist.separator" combine="interleave">
     <optional>
@@ -140,9 +141,10 @@
     </optional>
   </define>
   <define name="attlist.label" combine="interleave">
-    <optional>
+    <choice>
       <attribute name="name"/>
-    </optional>
+      <attribute name="name"/>
+    </choice>
   </define>
   <define name="attlist.label" combine="interleave">
     <optional>
@@ -211,7 +213,7 @@
     </element>
   </define>
   <define name="attlist.newline" combine="interleave">
-    <empty/>
+    <attribute name="id"/>
   </define>
   <define name="notebook">
     <element name="notebook">
@@ -245,7 +247,7 @@
         <choice>
           <ref name="image"/>
           <ref name="separator"/>
-          <ref name="labe"/>
+          <ref name="label"/>
           <ref name="newline"/>
           <ref name="notebook"/>
           <ref name="group"/>
@@ -271,6 +273,12 @@
       <attribute name="col" a:defaultValue="4"/>
     </optional>
   </define>
+  <define name="attlist.page" combine="interleave">
+    <choice>
+      <attribute name="name"/>
+      <attribute name="id"/>
+    </choice>
+  </define>
   <define name="group">
     <element name="group">
       <ref name="attlist.group"/>
@@ -278,7 +286,7 @@
         <choice>
           <ref name="image"/>
           <ref name="separator"/>
-          <ref name="labe"/>
+          <ref name="label"/>
           <ref name="newline"/>
           <ref name="notebook"/>
           <ref name="group"/>
@@ -329,9 +337,12 @@
       <attribute name="col" a:defaultValue="4"/>
     </optional>
   </define>
+  <define name="attlist.group" combine="interleave">
+    <attribute name="id"/>
+  </define>
   <define name="hpaned">
     <element name="hpaned">
-      <ref name="attlist.hpaned"/>
+      <ref name="attlist.paned"/>
       <optional>
         <ref name="child1"/>
       </optional>
@@ -340,19 +351,9 @@
       </optional>
     </element>
   </define>
-  <define name="attlist.hpaned" combine="interleave">
-    <optional>
-      <attribute name="colspan" a:defaultValue="4"/>
-    </optional>
-  </define>
-  <define name="attlist.hpaned" combine="interleave">
-    <optional>
-      <attribute name="position"/>
-    </optional>
-  </define>
   <define name="vpaned">
     <element name="vpaned">
-      <ref name="attlist.vpaned"/>
+      <ref name="attlist.paned"/>
       <optional>
         <ref name="child1"/>
       </optional>
@@ -361,24 +362,27 @@
       </optional>
     </element>
   </define>
-  <define name="attlist.vpaned" combine="interleave">
+  <define name="attlist.paned" combine="interleave">
     <optional>
       <attribute name="colspan" a:defaultValue="4"/>
     </optional>
   </define>
-  <define name="attlist.vpaned" combine="interleave">
+  <define name="attlist.paned" combine="interleave">
     <optional>
       <attribute name="position"/>
     </optional>
   </define>
+  <define name="attlist.paned" combine="interleave">
+    <attribute name="id"/>
+  </define>
   <define name="child1">
     <element name="child1">
-      <ref name="attlist.child1"/>
+      <ref name="attlist.child"/>
       <zeroOrMore>
         <choice>
           <ref name="image"/>
           <ref name="separator"/>
-          <ref name="labe"/>
+          <ref name="label"/>
           <ref name="newline"/>
           <ref name="notebook"/>
           <ref name="group"/>
@@ -389,17 +393,14 @@
       </zeroOrMore>
     </element>
   </define>
-  <define name="attlist.child1" combine="interleave">
-    <empty/>
-  </define>
   <define name="child2">
     <element name="child2">
-      <ref name="attlist.child2"/>
+      <ref name="attlist.child"/>
       <zeroOrMore>
         <choice>
           <ref name="image"/>
           <ref name="separator"/>
-          <ref name="labe"/>
+          <ref name="label"/>
           <ref name="newline"/>
           <ref name="notebook"/>
           <ref name="group"/>
@@ -410,8 +411,8 @@
       </zeroOrMore>
     </element>
   </define>
-  <define name="attlist.child2" combine="interleave">
-    <empty/>
+  <define name="attlist.child" combine="interleave">
+    <attribute name="id"/>
   </define>
   <define name="data">
     <element name="data">
@@ -427,7 +428,22 @@
   <define name="xpath">
     <element name="xpath">
       <ref name="attlist.xpath"/>
-      <ref name="any"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="image"/>
+          <ref name="separator"/>
+          <ref name="label"/>
+          <ref name="newline"/>
+          <ref name="notebook"/>
+          <ref name="group"/>
+          <ref name="hpaned"/>
+          <ref name="vpaned"/>
+          <ref name="action"/>
+          <ref name="page"/>
+          <ref name="child1"/>
+          <ref name="child2"/>
+        </choice>
+      </zeroOrMore>
     </element>
   </define>
   <define name="attlist.xpath" combine="interleave">
@@ -448,7 +464,7 @@
   <define name="action" combine="choice">
     <notAllowed/>
   </define>
-  <define name="labe" combine="choice">
+  <define name="label" combine="choice">
     <notAllowed/>
   </define>
   <start>
@@ -458,20 +474,4 @@
       <ref name="label"/>
     </choice>
   </start>
-  <define name="any">
-    <zeroOrMore>
-      <choice>
-        <element>
-          <anyName/>
-          <zeroOrMore>
-            <attribute>
-              <anyName/>
-            </attribute>
-          </zeroOrMore>
-          <ref name="any"/>
-        </element>
-        <text/>
-      </choice>
-    </zeroOrMore>
-  </define>
 </grammar>
diff --git a/trytond/ir/ui/form.rnc b/trytond/ir/ui/form.rnc
index 1bebb46494..d64c3211cf 100644
--- a/trytond/ir/ui/form.rnc
+++ b/trytond/ir/ui/form.rnc
@@ -50,7 +50,7 @@ attlist.y &= empty
 
 label = element label { attlist.label, empty }
 attlist.label &= [ a:defaultValue = "" ] attribute string { text }?
-attlist.label &= attribute name { text }?
+attlist.label &= ( attribute name { text } | attribute id { text } )
 attlist.label &= attribute states { text }?
 attlist.label &= [ a:defaultValue = "0.0" ] attribute align { text }?
 attlist.label &=
@@ -122,7 +122,7 @@ attlist.field &=
     | "right_to_left"
     | "bottom_to_top"
     | "top_to_bottom"
-  }
+  }?
 attlist.field &= attribute spell { text }?
 image = element image { attlist.image, empty }
 attlist.image &= attribute name { text }
@@ -134,7 +134,7 @@ attlist.image &= attribute help { text }?
 attlist.image &= attribute states { text }?
 separator = element separator { attlist.separator, empty }
 attlist.separator &= [ a:defaultValue = "" ] attribute string { text }?
-attlist.separator &= attribute name { text }?
+attlist.separator &= ( attribute name { text } | attribute id { text} )
 attlist.separator &= attribute states { text }?
 attlist.separator &=
   [ a:defaultValue = "0.0" ] attribute align { text }?
@@ -181,7 +181,7 @@ attlist.page &= attribute angle { text }?
 attlist.page &=
   [ a:defaultValue = "Unknown" ] attribute string { text }?
 attlist.page &= [ a:defaultValue = "4" ] attribute col { text }?
-attlist.page &= attribute name { text }?
+attlist.page &= ( attribute name { text } | attribute id { text } )
 attlist.page &= attribute states { text }?
 group =
   element group {
@@ -204,18 +204,19 @@ attlist.group &=
 attlist.group &= [ a:defaultValue = "1" ] attribute fill { "0" | "1" }?
 attlist.group &= [ a:defaultValue = "1" ] attribute rowspan { text }?
 attlist.group &= [ a:defaultValue = "4" ] attribute col { text }?
+attlist.group &= ( attribute name { text } | attribute id { text } )
 
-hpaned = element hpaned { attlist.hpaned, child1?, child2? }
-attlist.hpaned &= [ a:defaultValue = "4" ] attribute colspan { text }?
-attlist.hpaned &= attribute position { text }?
+hpaned = element hpaned { attlist.paned, child1?, child2? }
 
-vpaned = element vpaned { attlist.vpaned, child1?, child2? }
-attlist.vpaned &= [ a:defaultValue = "4" ] attribute colspan { text }?
-attlist.vpaned &= attribute position { text }?
+vpaned = element vpaned { attlist.paned, child1?, child2? }
+
+attlist.paned &= [ a:defaultValue = "4" ] attribute colspan { text }?
+attlist.paned &= attribute position { text }?
+attlist.paned &= attribute id { text }
 
 child1 =
   element child1 {
-    attlist.child1,
+    attlist.child,
     (label
      | field
      | image
@@ -227,11 +228,10 @@ child1 =
      | hpaned
      | vpaned)*
   }
-attlist.child1 &= empty
 
 child2 =
   element child2 {
-    attlist.child2,
+    attlist.child,
     (label
      | field
      | image
@@ -243,21 +243,35 @@ child2 =
      | hpaned
      | vpaned)*
   }
-attlist.child2 &= empty
+
+attlist.child &= attribute id { text }
 
 data = element data { attlist.data, xpath* }
 attlist.data &= empty
 
-xpath = element xpath { attlist.xpath, any }
+xpath = element xpath { attlist.xpath,
+    (label
+    | field
+    | image
+    | separator
+    | newline
+    | button
+    | notebook
+    | group
+    | hpaned
+    | vpaned
+    | form
+    | tree
+    | graph
+    | x
+    | y
+    | page
+    | child1
+    | child2)*
+  }
 attlist.xpath &= attribute expr { text }
 attlist.xpath &=
   [ a:defaultValue = "inside" ]
   attribute position { "inside" | "replace" | "after" | "before" }?
 
-any =
-  (element * {
-     attribute * { text }*,
-     any
-   }
-   | text)*
 start = data | form
diff --git a/trytond/ir/ui/form.rng b/trytond/ir/ui/form.rng
index 326aa9ccb6..9c5f00384a 100644
--- a/trytond/ir/ui/form.rng
+++ b/trytond/ir/ui/form.rng
@@ -79,12 +79,12 @@
   </define>
   <define name="attlist.tree" combine="interleave">
     <optional>
-       <attribute name="fill" a:defaultValue="0">
-          <choice>
-            <value>0</value>
-            <value>1</value>
-          </choice>
-       </attribute>
+      <attribute name="fill" a:defaultValue="0">
+        <choice>
+          <value>0</value>
+          <value>1</value>
+        </choice>
+      </attribute>
     </optional>
   </define>
   <define name="graph">
@@ -163,9 +163,10 @@
     </optional>
   </define>
   <define name="attlist.label" combine="interleave">
-    <optional>
+    <choice>
       <attribute name="name"/>
-    </optional>
+      <attribute name="id"/>
+    </choice>
   </define>
   <define name="attlist.label" combine="interleave">
     <optional>
@@ -502,9 +503,10 @@
     </optional>
   </define>
   <define name="attlist.separator" combine="interleave">
-    <optional>
+    <choice>
       <attribute name="name"/>
-    </optional>
+      <attribute name="id"/>
+    </choice>
   </define>
   <define name="attlist.separator" combine="interleave">
     <optional>
@@ -665,9 +667,10 @@
     </optional>
   </define>
   <define name="attlist.page" combine="interleave">
-    <optional>
+    <choice>
       <attribute name="name"/>
-    </optional>
+      <attribute name="id"/>
+    </choice>
   </define>
   <define name="attlist.page" combine="interleave">
     <optional>
@@ -733,9 +736,15 @@
       <attribute name="col" a:defaultValue="4"/>
     </optional>
   </define>
+  <define name="attlist.group" combine="interleave">
+    <choice>
+      <attribute name="name"/>
+      <attribute name="id"/>
+    </choice>
+  </define>
   <define name="hpaned">
     <element name="hpaned">
-      <ref name="attlist.hpaned"/>
+      <ref name="attlist.paned"/>
       <optional>
         <ref name="child1"/>
       </optional>
@@ -744,19 +753,9 @@
       </optional>
     </element>
   </define>
-  <define name="attlist.hpaned" combine="interleave">
-    <optional>
-      <attribute name="colspan" a:defaultValue="4"/>
-    </optional>
-  </define>
-  <define name="attlist.hpaned" combine="interleave">
-    <optional>
-      <attribute name="position"/>
-    </optional>
-  </define>
   <define name="vpaned">
     <element name="vpaned">
-      <ref name="attlist.vpaned"/>
+      <ref name="attlist.paned"/>
       <optional>
         <ref name="child1"/>
       </optional>
@@ -765,19 +764,22 @@
       </optional>
     </element>
   </define>
-  <define name="attlist.vpaned" combine="interleave">
+  <define name="attlist.paned" combine="interleave">
     <optional>
       <attribute name="colspan" a:defaultValue="4"/>
     </optional>
   </define>
-  <define name="attlist.vpaned" combine="interleave">
+  <define name="attlist.paned" combine="interleave">
     <optional>
       <attribute name="position"/>
     </optional>
   </define>
+  <define name="attlist.paned" combine="interleave">
+    <attribute name="id"/>
+  </define>
   <define name="child1">
     <element name="child1">
-      <ref name="attlist.child1"/>
+      <ref name="attlist.child"/>
       <zeroOrMore>
         <choice>
           <ref name="label"/>
@@ -794,12 +796,9 @@
       </zeroOrMore>
     </element>
   </define>
-  <define name="attlist.child1" combine="interleave">
-    <empty/>
-  </define>
   <define name="child2">
     <element name="child2">
-      <ref name="attlist.child2"/>
+      <ref name="attlist.child"/>
       <zeroOrMore>
         <choice>
           <ref name="label"/>
@@ -816,8 +815,8 @@
       </zeroOrMore>
     </element>
   </define>
-  <define name="attlist.child2" combine="interleave">
-    <empty/>
+  <define name="attlist.child" combine="interleave">
+    <attribute name="id"/>
   </define>
   <define name="data">
     <element name="data">
@@ -833,7 +832,28 @@
   <define name="xpath">
     <element name="xpath">
       <ref name="attlist.xpath"/>
-      <ref name="any"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="label"/>
+          <ref name="field"/>
+          <ref name="image"/>
+          <ref name="separator"/>
+          <ref name="newline"/>
+          <ref name="button"/>
+          <ref name="notebook"/>
+          <ref name="group"/>
+          <ref name="hpaned"/>
+          <ref name="vpaned"/>
+          <ref name="form"/>
+          <ref name="tree"/>
+          <ref name="graph"/>
+          <ref name="x"/>
+          <ref name="y"/>
+          <ref name="page"/>
+          <ref name="child1"/>
+          <ref name="child2"/>
+        </choice>
+      </zeroOrMore>
     </element>
   </define>
   <define name="attlist.xpath" combine="interleave">
@@ -851,22 +871,6 @@
       </attribute>
     </optional>
   </define>
-  <define name="any">
-    <zeroOrMore>
-      <choice>
-        <element>
-          <anyName/>
-          <zeroOrMore>
-            <attribute>
-              <anyName/>
-            </attribute>
-          </zeroOrMore>
-          <ref name="any"/>
-        </element>
-        <text/>
-      </choice>
-    </zeroOrMore>
-  </define>
   <start>
     <choice>
       <ref name="data"/>
diff --git a/trytond/ir/ui/graph.rnc b/trytond/ir/ui/graph.rnc
index 4b299e786e..526cb6575e 100644
--- a/trytond/ir/ui/graph.rnc
+++ b/trytond/ir/ui/graph.rnc
@@ -26,15 +26,13 @@ attlist.field &= attribute color { text }?
 attlist.field &= attribute widget { "float_time" }?
 data = element data { attlist.data, xpath+ }
 attlist.data &= empty
-xpath = element xpath { attlist.xpath, any }
+xpath = element xpath { attlist.xpath,
+    (graph
+    | x
+    | y)*
+  }
 attlist.xpath &= attribute expr { text }
 attlist.xpath &=
   [ a:defaultValue = "inside" ]
   attribute position { "inside" | "replace" | "after" | "before" }?
 start = data | graph
-any =
-  (element * {
-     attribute * { text }*,
-     any
-   }
-   | text)*
diff --git a/trytond/ir/ui/graph.rng b/trytond/ir/ui/graph.rng
index 22efa7454b..a7b691bbc8 100644
--- a/trytond/ir/ui/graph.rng
+++ b/trytond/ir/ui/graph.rng
@@ -134,7 +134,13 @@
   <define name="xpath">
     <element name="xpath">
       <ref name="attlist.xpath"/>
-      <ref name="any"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="graph"/>
+          <ref name="x"/>
+          <ref name="y"/>
+        </choice>
+      </zeroOrMore>
     </element>
   </define>
   <define name="attlist.xpath" combine="interleave">
@@ -158,20 +164,4 @@
       <ref name="graph"/>
     </choice>
   </start>
-  <define name="any">
-    <zeroOrMore>
-      <choice>
-        <element>
-          <anyName/>
-          <zeroOrMore>
-            <attribute>
-              <anyName/>
-            </attribute>
-          </zeroOrMore>
-          <ref name="any"/>
-        </element>
-        <text/>
-      </choice>
-    </zeroOrMore>
-  </define>
 </grammar>
diff --git a/trytond/ir/ui/menu.xml b/trytond/ir/ui/menu.xml
index 1a2c4788a2..15b2238991 100644
--- a/trytond/ir/ui/menu.xml
+++ b/trytond/ir/ui/menu.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
-<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of this repository contains the full copyright notices and license terms. -->
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
 <tryton>
     <data>
         <record model="ir.ui.view" id="menu_view_tree_tree">
diff --git a/trytond/ir/ui/tree.rnc b/trytond/ir/ui/tree.rnc
index 04f81eeabe..1e4a03789b 100644
--- a/trytond/ir/ui/tree.rnc
+++ b/trytond/ir/ui/tree.rnc
@@ -51,7 +51,7 @@ attlist.field &=
     | "right_to_left"
     | "bottom_to_top"
     | "top_to_bottom"
-  }
+  }?
 button = element button { attlist.button, empty }
 attlist.button &= attribute help { text }?
 attlist.button &=
@@ -64,15 +64,13 @@ attlist.button &= attribute name { text }
 attlist.button &= attribute states { text }?
 data = element data { attlist.data, xpath+ }
 attlist.data &= empty
-xpath = element xpath { attlist.xpath, any }
+xpath = element xpath { attlist.xpath,
+    (field
+    | button
+    )*
+  }
 attlist.xpath &= attribute expr { text }
 attlist.xpath &=
   [ a:defaultValue = "inside" ]
   attribute position { "inside" | "replace" | "after" | "before" }?
 start = tree | data
-any =
-  (element * {
-     attribute * { text }*,
-     any
-   }
-   | text)*
diff --git a/trytond/ir/ui/tree.rng b/trytond/ir/ui/tree.rng
index 41647878b6..70d92618f3 100644
--- a/trytond/ir/ui/tree.rng
+++ b/trytond/ir/ui/tree.rng
@@ -43,12 +43,12 @@
   </define>
   <define name="attlist.tree" combine="interleave">
     <optional>
-       <attribute name="fill" a:defaultValue="0">
-          <choice>
-            <value>0</value>
-            <value>1</value>
-          </choice>
-       </attribute>
+      <attribute name="fill" a:defaultValue="0">
+        <choice>
+          <value>0</value>
+          <value>1</value>
+        </choice>
+      </attribute>
     </optional>
   </define>
   <define name="attlist.tree" combine="interleave">
@@ -207,7 +207,12 @@
   <define name="xpath">
     <element name="xpath">
       <ref name="attlist.xpath"/>
-      <ref name="any"/>
+      <zeroOrMore>
+        <choice>
+          <ref name="field"/>
+          <ref name="button"/>
+        </choice>
+      </zeroOrMore>
     </element>
   </define>
   <define name="attlist.xpath" combine="interleave">
@@ -231,20 +236,4 @@
       <ref name="data"/>
     </choice>
   </start>
-  <define name="any">
-    <zeroOrMore>
-      <choice>
-        <element>
-          <anyName/>
-          <zeroOrMore>
-            <attribute>
-              <anyName/>
-            </attribute>
-          </zeroOrMore>
-          <ref name="any"/>
-        </element>
-        <text/>
-      </choice>
-    </zeroOrMore>
-  </define>
 </grammar>
diff --git a/trytond/res/group.xml b/trytond/res/group.xml
index 974d5a28ff..fb4e4faa4c 100644
--- a/trytond/res/group.xml
+++ b/trytond/res/group.xml
@@ -18,11 +18,11 @@ this repository contains the full copyright notices and license terms. -->
                     <label name="name"/>
                     <field name="name"/>
                     <notebook>
-                        <page string="_Group" col="2">
+                        <page string="Group" col="2" id="group">
                             <separator name="users" colspan="2"/>
                             <field name="users" colspan="2"/>
                         </page>
-                        <page string="_Security" col="1">
+                        <page string="Security" col="1" id="security">
                             <separator name="model_access"/>
                             <field name="model_access"/>
                             <separator name="menu_access"/>
diff --git a/trytond/res/request.xml b/trytond/res/request.xml
index 4c714c5b84..9688cf3018 100644
--- a/trytond/res/request.xml
+++ b/trytond/res/request.xml
@@ -32,7 +32,7 @@
                     <field name="act_from"/>
                     <label name="act_to"/>
                     <field name="act_to"/>
-                    <group colspan="2" col="4">
+                    <group colspan="2" col="4" id="active_ref">
                         <label name="active"/>
                         <field name="active"/>
                         <label name="references"/>
@@ -43,13 +43,13 @@
                     <label name="priority"/>
                     <field name="priority"/>
                     <notebook colspan="6">
-                        <page string="_Request">
+                        <page string="Request" id="request">
                             <separator name="body" colspan="4"/>
                             <field name="body" colspan="4"/>
                             <field name="history" colspan="4"/>
                             <label name="trigger_date"/>
                             <field name="trigger_date"/>
-                            <group col="2" colspan="2">
+                            <group col="2" colspan="2" id="buttons">
                                 <button name="request_send"
                                     states="{'invisible': '''state not in ('draft', 'chatting')''', 'readonly': '''act_from != _user'''}"
                                     string="Send" type="object"/>
@@ -59,13 +59,13 @@
                             </group>
                             <label name="state"/>
                             <field name="state"/>
-                            <group col="3" colspan="2">
+                            <group col="3" colspan="2" id="button">
                                 <button name="request_close"
                                     states="{'invisible': '''state not in ('waiting', 'draft', 'chatting')'''}"
                                     string="Close" type="object"/>
                             </group>
                         </page>
-                        <page string="_References" col="1">
+                        <page string="References" col="1" id="references">
                             <field name="references"/>
                         </page>
                     </notebook>
diff --git a/trytond/res/user.xml b/trytond/res/user.xml
index aeb35923a5..aaea8ad507 100644
--- a/trytond/res/user.xml
+++ b/trytond/res/user.xml
@@ -22,7 +22,7 @@ this repository contains the full copyright notices and license terms. -->
                     <label name="active"/>
                     <field name="active"/>
                     <notebook colspan="4">
-                        <page string="User">
+                        <page string="User" id="user">
                             <label name="login"/>
                             <field name="login"/>
                             <label name="password"/>
@@ -38,13 +38,13 @@ this repository contains the full copyright notices and license terms. -->
                             <separator name="signature" colspan="4"/>
                             <field name="signature" colspan="4"/>
                         </page>
-                        <page string="Security" col="1">
+                        <page string="Security" col="1" id="security">
                             <separator name="groups"/>
                             <field name="groups"/>
                             <separator name="rule_groups"/>
                             <field name="rule_groups"/>
                         </page>
-                        <page string="Preferences" col="2">
+                        <page string="Preferences" col="2" id="preferences">
                             <label name="language"/>
                             <field name="language" widget="selection"/>
                             <label name="timezone"/>
@@ -110,11 +110,11 @@ this repository contains the full copyright notices and license terms. -->
                 <![CDATA[
                 <form string="Add Users" col="2">
                     <image name="tryton-dialog-information"/>
-                    <group col="1">
+                    <group col="1" id="labels">
                         <label string="You can now add some users into the system."
-                            align="0.0"/>
+                            align="0.0" id="add"/>
                         <label string="Be careful that the login must be unique!"
-                            align="0.0"/>
+                            align="0.0" id="carefull"/>
                     </group>
                 </form>
                 ]]>