[MadBlaster]

If you have 2GB or less of ram and maybe no page file, I suppose you could be crashing the game with some of those mod maps that are very large. When you start adding objects, I think it takes even more memory. I would get a freeware program that allows you to monitor page file and ram usage in real time when you open up those maps. Something that overlays the game. The one I use is called tinyresmeter, but there are plenty of others. I think I found it on CNET.