So, what your asking for is a 3d model of a face that you can import into disastercam? If you feel the method on vectric was over your head, I'm afraid you might just find out that MC is far from friendly. My experiences with it always is, anyhow. It seems to be very finicky with imported models. My best results importing have been with nurbs models, which happens to be the way most models are NOT created. They instead are usually made using a polygonal mesh. I have played with the fully functional trial version of MESHCAM, and was impressed. It might do what you want, with a whole lot less headache. Download a model, open it, make your toolpaths, go machine it. If you know a reliable way of importing surfaces from a poly model easily with MC, I'm all ears. Please, do tell.
Now, on the other hand, if your trying to use Mastercam Art, and using a picture or a clipart image of a face, that's a different method and can of worms altogether. Good luck on your quest.