I have a similar problem but think that it is the trial version of Mach 3 conflicting with the licensed version. The reason I think this is that when I use start via a desktop shortcut or the loader, I get different opening screens. One displays version x.x and is the trial version screen to the best of my recollection. The other is a colour Version 2 screen.
I have previously uninstalled Mach 3 via the windows control panel, and reinstalled, but the problem persists. The program will run a file, but then tends to freeze, especially after standing idle for a while and require a hard reset.
If there is an artifact process, how do i get rid of it?
Or are there other likely explanations?