Increase the contrast so it's more black and white. I will nab this and see if I can make it work. Map it to the one sided square and place the square on the left side of the poser scene. Then select the square and 'create spotlight' this will ensure you have a light pointing directly at the square. This should cast shadows on the center if it works. If you still can't see it tryturning the other non spotlights off. That should tell for sure.

"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