On certain missions the game will often have a graphics-related crash, and will slow to a bloody crawl, making certain missions completely unbeatable. No setting changes fix this.
On the "alternative" arc, it's the (first?) cap-ship vs. fight, and on the second chapter of the main arc it's the one where you're defending a base and a Tethys that's evacuating it.
I am using 3.6.18 final, running Win8 x64, and using a HIS HD5670, but I doubt it has anything to do with my graphics card because this crash carries through that entire instance of FSO. Meaning if I quit and open up any other mission in the same instance, it's still a bloody crawl.
This is both before and after the patch.
I'll try 3.7RC2 and come back with an update.
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Okay, I tried 3.7 and it also crashes. It runs a lot smoother, but I still get that crash.
Somehow I think it may not have to do with DE, seeings that it carries over to other missions, but stops if my ship gets canned.