>The 2nd approach is probably harder to test. :)

Well, for me, I just can't make anything work as soon as I sub class from the main class in the sub EXE. I posted more information in the other thread a few minutes ago. Basically, the only approach I didn't try is to dump on the production server the main class and make a reference to the physical path of that class from the main EXE. I would then assume the sub EXE could create an instance of a sub class without hanging. Presently, there is a bug in VFP that makes the sub EXE hang and maybe using that approach it won't. But my concern is about performance. Will that still be as fast?