Usage of the Extension Point - Build Result Delete Participants

I have published a custom contribution to the build result and also have a contribution provider so it appears in the Build Results view in its own tab(it retreives a zip file via ftp from a host, unzips it locally and formats the files for viewing). The file is too large to store as a contribution as discussed in my other forum questions. That all works great, no issues with that part.
Now I am attempting to delete the files when the build result is deleted. I want to delete the contribution file(small file with ftp connection info) in the repository attached to the result, the zip file residing on the host via ftp and the locally
unzipped files.
I have written a Build Result Delete Participant, but it doesn't seem to get control at time of delete. It seems via the FAQ page that is by design. That it is only marked for deletion and deleted later? Therefore I cannot do all I want to do? I can only delete the contribution file in the respos?
I modeled this after the CompileContributionDeleteParticipant. But I not actually deleting the file yet, just seeing if it gets control before I implement all the other logic. Can I do what I want to do? Is my coding correct and understanding correct? Also I would like to cause a dialog to pop up during the delete because we also have some user specific options the user can select as to what and how to clean various items form the host that were created via the build process. It seems like that cannot be done with the participant if it indeed runs at a later time.
Are there any other ways to accomplish what I want to do. Is there a way to add a custom action off the context menu for a build result?
Also I get a waring when I code the

         <prerequisites>
            <requiredService interface="com.ibm.team.repository.service.IRepositoryItemService"/>
         </prerequisites>

provided in the sample that it is not a legal tag for extensionService so I removed it.

<plugin>
   <extension
         point="com.ibm.team.build.ui.requestBuildDialogSections">
      <requestBuildDialogSection
         class="com.ibm.sdwb.zbuild.rtc.buildengine.ui.editors.ZBuildRequestBuildSectionFactory"
         order="300"/>
   </extension>
    <extension
         point="com.ibm.team.build.ui.buildContributionProviders">
      <buildContributionProvider
         id="com.ibm.sdwb.zbuild.rtc.ui.editors.ZBuildBuildResultContributionProviderDelegate"
         class="com.ibm.sdwb.zbuild.rtc.buildengine.ui.editors.ZBuildBuildResultContributionProviderDelegate"
         name="zBuild Files"/>         
   </extension>
<extension
      point="com.ibm.team.build.service.buildResultDeleteParticipants">
   <buildResultDeleteParticipant
         id="com.ibm.sdwb.zbuild.rtc.ui.participants.ZBuildContributionDeleteParticipant">
      <extensionService
            componentId="com.ibm.team.build"
            implementationClass="com.ibm.sdwb.zbuild.rtc.ui.participants.ZBuildContributionDeleteParticipant">
      </extensionService>
   </buildResultDeleteParticipant>
</extension>
</plugin>

public class ZBuildContributionDeleteParticipant
      extends AbstractBuildContributionDeleteParticipant
{

   public String[] getContributionTypeIdsOfInterest()
   {
      return new String[] { "zBuildResult" };
   }

   /*
    * (non-Javadoc) Intentionally not documented. See parent.
    */
   protected void doDelete( IBuildResultContribution buildResultContribution )
         throws TeamRepositoryException
   {
      System.out.println( "ZBuildContributionDeleteParticipant::doDelete Entry" );
      
//      ICompileContributionHandle handle = (ICompileContributionHandle)buildResultContribution
//            .getExtendedContribution();

      IRepositoryItemService repoService = getService( IRepositoryItemService.class );

      // try {
      // // fetch the compile packages and delete them
      // CompileContribution compileContribution = (CompileContribution) repoService.fetchItem(handle,
      // new String[] { ICompileContribution.PROPERTY_COMPILE_PACKAGES });
      // List<ICompilePackageHandle> packages = compileContribution.getCompilePackages();
      // deletePackages(packages, repoService);
      // // have to call the base class method to delete the compile
      // // contribution itself
      // super.doDelete(buildResultContribution);
      //
      // } catch (ItemNotFoundException exception) {
      // // The build result contribution reference an item that does not
      // // exist. Ignore it and continue.
      // handleItemNotFound(handle, exception);
      // }

      super.doDelete( buildResultContribution );
      System.out.println( "ZBuildContributionDeleteParticipant::doDelete Exit" );

   }