Craig
As far as what you asking I beleive you asking about a background. In zbrush texture is something that is laid over your model and does not change the geometry and would not do anything in regards to a ptn. You can use alphas to give your actual model a textured look..think this what you are refering to. In this example of the attached net alpha i used this in one of my patterns http://carvemore.com/store/fallriverbank.html to give the fishing net the "texture" or netting look. To give your model a textured look you have to do it within zbrush as sculpting using the alphas. More info check out the tutorials on alpha's and projection master at pixologic. Hope this helps you.