I've got M4 loaded and go to the texture room, then select the "SkinFace".  It has the default texture map of the face, then I try the "Multiply" and use the "Noise function: Fractal Noise" for Source 2.  (The default texture map becomes Source 1).  The idea is a sort of plague, and it looks pretty good, some black nasty marks on the face.  But when I animate the head, the black marks slide around on the face.  I tired some different mappings (parametric, spherical), and also changing the "Space" in the fractal noise (local, global, UV), and also "Add" instead of "Multiply",  no luck.  Ideas?  I am a complete novice in the texture room, so you cannot be too basic.