I have been using Punch! for years now, and have never had this problem. I like to put the screen on split 2D/3D view and after I'm into it for a bit, the 3D screen goes completely black and the file gets corrupted.

I really hope I don't have to buy a brand new computer just so I can use this program.

Any help would be greatly appreciated.

I had the same issue. I too found it only happens when some objects, usually kitchen cabinets, are loaded and split screen is used. I had just bought a state of the art PC with a very expensive video card because I had slow rendering with my older machine, but no other issues. I went back and forth with the PC company and Punch support. Finally the video card manufacture, (Nvidia), came up with a driver that worked. I cant say it is totally fixed but I have had only 1 crash in 100 hours of use rather then more then I could count. I also no longer wind up with hours of work destroyed when it does happen.