Ok, I'm working on some skin settings....and I did a quick test render, and there are these big splotches on the skin toward the back. 
I don't have texture filtering on.  I'm not using IBL or AO in lighting, but there is SSS and AO on the skin.  2 infinite lights, set to about mid-strength, grey lighting.

Sitemail | Freestuff | Craftythings | Youtube|

Knowledge is knowing a tomato is a fruit. Wisdom is not putting it into a fruit salad.

Ok, second try at uploading the image.  *sigh*

Sitemail | Freestuff | Craftythings | Youtube|

Knowledge is knowing a tomato is a fruit. Wisdom is not putting it into a fruit salad.

Increase the "Shadow Min Bias"  on any lights you have casting shadows.
Do one light at a time until the artifacts disappear.

The cause (if your interested) is non-planar polygons.

hmm....would that happen, even if I have shadows turned off in the render?  (I'm relatively new to P6...I've had 5 for years, but just got 6 in September)

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Knowledge is knowing a tomato is a fruit. Wisdom is not putting it into a fruit salad.

yep, I can confirm there are no shadows in the above. noel, non-planar means "not flat"? it means they're curved?

It's the skin AO causing the problem, if it's not the lights.  There should be a bias setting on the AO node, which may need to be increased.  To be absolutely sure, unplug the AO node and do a render without it.  If they go away, then you know.

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Tools :  3dsmax 2015, Daz Studio 4.6, PoserPro 2012, Blender v2.74

System: Pentium QuadCore i7, under Win 8, GeForce GTX 780 / 2GB GPU.

Increase the RayBias setting on the AO node to 0.1 or so. You may need to increase the MaxDist as well and possibly DECREASE the strength slightly, to perhaps .9 or .85. But the RayBias setting alone should fix it.