This might have something to do with what's called 'crosstalk'. There was a file created called a 'null' which fixes some problems from that. http://www.daz3d.com/pages/faq/techtips/crosstalk.html All that stuff also could just be too complex for your resources to render but I'd try the null thing first.

"Your work is to keep cranking the flywheel that turns the gears that spin the belt in the engine of belief that keeps you and your desk in midair."

Annie Dillard