I have read the tutorials on using color math and an second image map...I got this to work for a tattoo on the front of the body, but the back does not seem to work near the buttocks. I am using the pretty3d Base from Mytilus and it seems that nothing below the waist will rendor the tattoo. I even tiled it on both skin torso and skin hip materials... I tiled it just to see if it would do it as it places the tattoo alll over the image map. So what am I doing wrong?

I figured it out. Turns out the Pretty3d base has a Skin Hip, that controlled the hip area, I was doing all of my work on SkinTorso. Here is the setup I used. The work is out on the gallery called "A View Of A Too"