When I import a black and white png image that I want to use to sculpt with, it creates the following maps: all, color, alpha, depth, specl, erase. But I've noticed that only all and color have the actual stamp in it, the others, including alpha are just blank boxes, so when I try to use them with the airbrush, it doesn't do anything. How do I get the program to automatically create an alpha channel as well? I've watched a lot of tutorials that talk about dragging a jpg into the brush panel so I assume it can be done.