This error only occurs when using the Embedded Editor. The modal dialog of the Custom Change Request works as expected. However, the Embedded Editor does not open at all, but instead generates the following message
This is followed by Internal application : null error.
If the Embedded Editor is switched off the modal dialog opens as expected.
The error is caused by an incorrect XML tag in ChangeRequest.propertyeditor.xml
The following tag
<propertyeditor name="Change Request Editor" version="1.0">
<propertyeditor name="Change Request Editor" version="1.1">
Update this file to use the correct version number, save the file, and restart the StarTeam CPC.
This should resolve the issue and the Embedded Editor should now display correctly.