Uh - I may be barking up the wrong tree, but it seems to me that if I change Diffuse_Value to something other than 1, then the color of the skin changes in renders (not in previews though).  Is there a reason why this is not a good idea in general?  And specific to AntoniaTiger's question, are you more interested in moving freckles and blemishes around (which I am, and will be wanting to figure out how to do other than just modifying the base texture) or changing color and brightness?

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