Looks like you may be getting an access violation error: Try steering your jobs towards one execute machine and use Process Monitor (from the Windows Sysinternals toolset) to monitor the activity of the condor_exec process, it should tell you when you hit a problem (as well as where and why).
Michael,
I also find USE_VISIBLE_DESKTOP=True invaluable when trying to trouble shoot runtime problems with Windows nodes. Setup one node as Ben suggests and target just that box. If your application quits quickly a batch wrapper that sleeps for some amount of time before actually running your real work can give you the minutes you need to get Process Monitor ready to attach to it.
- Ian