gwicks, firstly, the 3rd render is nice. A great "red" transitioning between the light and dark side of her thigh. The light side is too yellow IMO, and this is generally due to too much lighting in the scene. Real skin under heavy lighting goes very white, not yellow. Also, have you got the ambience incidence effect plugged in? The dark side of her thigh is too dark. Maybe wind the ambient red up a little. One of the weaknesses of this technique is that there is no ambient red on directly backfacing (to the main light) poly's. Will find a way around this one day.... On to your problem at hand. I had never seen the effects you are getting (although I don't use r/t shadows that often). One thought that comes to mind is that it's being caused by the displacement map. Try switching that off and see if it helps. Seems to be a shadow problem, so try depth-mapped shadows instead of r/t. Also try turning up the shadow min bias.

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