I'm trying to make it look like the skin has been scratched. I know it's not lined up correctly, but do the colors look okay? I can barely draw a stick figure (which is why I use Poser), so any suggestions would be appreciated.

Interesting. You probably should apply the scratch to the actual skin texture instead of postworking it. That way the shadows will look right. As is, the pink zones seem to be "bridges" across the spine valley. Also, you might experiment with a narrower layer of white on top of the wider pink; a scratch sometimes plows up some of the dead epidermis.

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way too pink. start with yer skin tone and add a darker red to it, then feather the edge with white.

perhaps a good bumpmap would help as well.