OK, there is a lot going on here....A couple of points (all based on my experience, rather than what might actually be factual). 1) If you have displacement bounds (FF setting) set the the displacement value in the mat room, you should get mesh breakage (unless the mat room node for displacement are passing a value of < 0 or > 1). In general, if you've got displacement bounds set correctly, any black spots will be caused by shadowing. 2) Min shadow bias....0 has always resulted in an object self shadowing itself in my renders. 0.3-0.4 seems to be the minimum level I can use to avoid this if I'm using displacement maps. 3) poly smoothing....IMO you should always have this on. It provides a true poly subdivisional surfacing, which should get rid of the sofa edge artifacts shown above. 4) AntoniaTiger....The effect you are getting above demonstrates one of the probs with displacement mapping in general (not specifically with Poser). It is not valid to simply plug white into a displacement map node. You need to build the displacement map in ZBrush, or another similar app - which will compensate for the poly edges in the map. Alternately, using a very low color or displacement value (as the RealSkinShaders does) gets around the issue.

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