A workaround.

If I add the following statement to before the abort command the program terminates correctly.

Code:
Send Popup Of oSDIPanel
Start_UI 

Runprogram Shell Background 'cmd.exe' '/D /C ""'

Abort
NB: I had to include the option 'Shell' for this to work.

However, you do get a screen flash but creating a very basic DataFlex program prevents this from happening.