[macstu23]

I had a similar problem when i first installed maps. Try mucking around with the advanced and video settings in options, if you havent already. Thats what i did and i dont get the problem now. They want to be on at least a medium level of detail, I'm fairly sure. Texture compression may have something to with it as well. Wish i could be more specific. I'm sure someone will have better knowledge than me. I'm assuming you have a reasonably decent video card...mines is only ge-force 2 but its good enough.