my attempt to test this has run into trouble..

I created a new parent(P), then created a new project (A), created a local enum, attribute,presentation, created a workitem(14). selected data from the enum,  all is ok.
then I created a NEWER project (P1) from the same template, with the field still missing (enum, attribute, presentation)
then I reparented project A using the new project (P1).
the fields in the workitem 14 for the local data appear on the Custom tab.. as expected

now I want to use the delta-config to define the local fields..
do one at a time

enum first

            <configuration-data-delta configuration-data-id="com.ibm.team.workitem.configuration.enumerations">
               <add-element>
                  <addition>
                     <enumeration attributeTypeId="com.id.workitem.enum.featurelist" name="Featurelist">
                        <literal default="true" null="true" id="com.id.workitem.enum.literal.l2" name="unassigned"/>
                        <literal id="com.id.workitem.enum.literal.l4" name="test1"  externalValue="test1"/>
                        <literal id="com.id.workitem.enum.literal.l6" name="test2"  externalValue="test2"/>
                     </enumeration>
                  </addition>
               </add-element>
            </configuration-data-delta>   

this saves without error.. switching back to the non-source process config view however shows as below, which seems to indicate some problem.

this forum tool needs a '&lt;code&gt; block element

this to me says, add an enumeration, add an attribute to hold it, and put it on the screen after the Category field.
in the defect record. (where ever default editor is).. this is cut/paste of the text here
https://jazz.net/wiki/bin/view/Main/ConfigurationDataDeltaUserDoc

but the field does appear on the custom tab.. so I must have misunderstood how to specify presentation placement
<code>
<configuration-data-delta configuration-data-id="com.ibm.team.workitem.configuration.workItemTypes">
   <add-element>
      <addition merge-depth="1">
         <customAttributes category="com.ibm.team.workitem.workItemType">
            <customAttribute id="com.xx.id.workitem.attribute.feature" name="Feature" type="com.xx.id.workitem.enum.featurelist"/>
         </customAttributes>
      </addition>
      <addition merge-depth="1">
         <attributeDefinitions>
            <attributeDefinition id="com.xx.id.workitem.attribute.feature" name="Feature" type="com.xx.id.workitem.enum.featurelist"/>
         </attributeDefinitions>
      </addition>
   </add-element>
</configuration-data-delta>
<configuration-data-delta configuration-data-id="com.ibm.team.workitem.editor.configuration.presentations">
     <add-element>
          &lt;path>
              &lt;section id="com.xx.tools.workitem.section.details">
                 <presentation attributeId="com.ibm.team.workitem.attribute.category"/>
              &lt;/section>
          &lt;/path>
          <addition location="after">
                 <presentation attributeId="com.xx.id.workitem.attribute.feature" 
                            kind="com.xx.id.workitem.enum.featurelist"/>                    
          </addition>
      </add-element>
 </configuration-data-delta>
</code>
here is the parent presentation section
<code>
&lt;section id="com.xx.tools.workitem.section.details">
                    <presentation attributeId="com.ibm.team.workitem.attribute.workitemtype" kind="com.ibm.team.workitem.kind.enumeration"/>
                    <presentation attributeId="com.ibm.team.workitem.attribute.category" kind="com.ibm.team.workitem.kind.internal.category"/>
                    <presentation attributeId="com.ibm.team.workitem.attribute.severity"
kind="com.ibm.team.workitem.kind.enumeration"/>
</code>
it appears correctly, on the wrong tab. so the enum, and the variable are correct, and the structure of the presentation is right.. just the anchor appears wrong..

well, I went back and cut/pasted the same text over again , and now it works!!

parent A, has enum X/attribute/presentation
    child of parent A, customizes enum X, enum section breaks away
parent B, removes enum X/attribute/presentation, as intended to be overridden in client
      updates enum Y with another value for all clients
child of parent A, now made to be child of Parent B.
      delete process xml (the breakaway copy)
      add delta config for definition of child representation of enum X/attribute/presentation
synchronize attributes for all existing workitems
      open existing worktitem, custom data appears with prior selection of enum
open new workitem, delta config custom data appears
update delta config
      open new workitem, new delta config
      open existing workitem, no delta config update
      synchronize attributes existing workitems
      open existing workitem
      update delta config present.

THIS is ENORMOUS news..  we can recover from breakaway!!!!..

please please, document this as the case and support it while you build the rest of the delta config support.

now there is a BAD side too.. if you have a child that breaks away, and you delete the process config and add the delta that overlaps/duplicate the (existing or new) parent.. you get a MERGE of both  so you get TWO fields on the presentation AND in the enum case, BOTH merged together.. quite ugly!!