(the indomitable mooch steps up to the plate again) .. okies. The latest movie introduces another good clue. The 'dribbling' effect at the bottom right corner of the model's mouth. Something's happening with the texture that isn't shadow related. Another clue is operaguy's reference to assorted shaders for the skin. Back to good ol' fashioned trouble-shooting, I think. Rather than whacking all settings up to the max, why not try 'simplify to clarify' (just made that up, but it sounds kinda profound, dontcha think?). So .. remove as many procedural shaders as you can. Render out to a series of stills, rather than direct to Quicktime. There are a number of apps that let you convert stills into a movie (last time I looked, anyway .. couple of years ago). Or, try rendering to AVI and use 'no compression' or, at least, a different codec or two. Try to get to a set up which has no artefacts. Then build complexity from there. Yes .. it'll be hard work, but then you'll be one of the new Poser animation experts. Yay!