N-5/Prudii

I guess you're talking about like in my Shadow Trooper - all I did was use the "overlay" function in GIMP and applied a bunch of layers of black over the white. Now after I did that it still had white splotches in the very bright areas, so I used the "Smudge" tool to blend the white into the alpha channel to make it look like highlights. You'll notice it in the picture, especially on the thighs and the middle of the nose.

I use overlay probably the most of any function and talk about it in my little tutorial . I'm sure you don't need the tut because of what I've seen you seem like an awesome skinner, but it at least shows you where the overlay function is

Hope this helps.