I've done about the same # of races as you. I have similar goals: (1) don't crash and (2) don't come in last.

I also think it is good to use these things as a learning experience. Go out with the goal to give it 110% and see how your body responds. Talk to people that know the course, try as hard as you can to stay close to the front (but not at the front) especially at the beginning. Once you lose contact with the main pack, it's hard to get back on. If you are concerned about the climbing, try to be at or near the front before so if you do happen to slide back then you can hop back on as you go over.

Be sure to get good sleep 2-3 night before the race, but don't worry about what happens the night before. Eat a good pre-race meal and make sure you are well hydrated. Don't let sudden cramps in your leg ruin an otherwise good day. I've seen that happen to other riders who didn't eat/drink properly right before their race. do a good warmup.