Went to play warhead today and I get a "game cannot be started...install limit reached". I've made a few changes, added ram, a hard drive, new vid card, I dual boot xp/vista64, that might count as well. Also I installed it on my sons comp, then swapped out vid cards. I guess hardware changes...
Just an fyi, the fs2 source code was released a few years ago and there has been many updates to the engine, as well as graphic mods, and new campaigns.
http://www.hard-light.net/forums/
If you guys want some more Freespace check out http://dynamic4.gamespy.com/~freespace/forums/index.php?s=?cat=37
The source code was released awhile ago and there has been many updates, looks fantastic. Lots of user made campaigns to be had as well.