>Just for testing, I want to change the screen resolution when running the app. I already have conditions so it knows whether it is being run in development or not. Just want to run at 800x600 at runtime, then back to default (1024x768) when it exits so I can be back in my normal development resolution. Is there a simple way to do this?

Try Change Video Display Mode in VFP File #9942 by the late Ed Rauh.

I haven't tried it myself, though.