debugging app exceptions?

Hi,

I am trying to debug an app and making good progress with on sorting out  
the dlls reqd. but now have an exception I dont know how to follow.

The progs own log ends with:

10:21:35 File C:\progs\natz\Program\dd10enum.dll: Version 7.0.0.2
10:21:35 File C:\progs\natz\Program\dmfc6.dll: Version 7.0.0.0
10:21:35 Exception thrown (d:\work\px\trouble\tests.cpp, 936).
10:21:35
10:21:35 Cannot find the file 'nstex50.dll'
10:21:35 QuickCheck Failed.
10:21:36 Final Termination


The "cannot find" is erroneous since it has found the file so I need to  
get more info on the exception , I did a WINEDEBUG="heap" and all seemed  
OK, I am a bit unsure where to go now.

Suggestions?

TIA