I fixed my problem with crashing by switching from HDR to Bloom and playing in windowed mode. I played for 6 hours (where does the time go?!?!) without a single crash and only minor shows of instability. What I'm wondering now is if there is a way to reduce the intensity of the bloom effect. The way it is now, during the day, the sun looks like it takes up 3/4s of the sky and skin practically glows.