thanks for the comments. I see what you mean with the bone protruding. I'll have a go adding a bit next time I mix some putty to see if I can get it to look reasonable.
About the skin being tight, it doesn't worry me that much. The problem, now that you mentioned it is that the face don't quite match the body. As in the face looks like the more loose skin type of zombie but the skin on the figure is still tight and fresh, if you get what I mean. oh well.... I'll keep that in mind for the next one (I have 3 more unfinished one on the desk)