Sorry I never replied to this. The problem is I can't remember what I did
I had searched the forums for ages and found a post by a guy suggesting people make changes to the view distance and some other settings, I still can't remember what/who/where, sorry about that, but it seemed to work.
I'm still having problems though (crashing mid-mission), might need to mess with my AGP settings again. Gonna be switching heatsink and some other things soon and that'll be a good day to do something like this as well. I'll report on any progress I have.
(Trying the -nomap thing too, I'll see what that does).