Can't texture paint in 3d window.

I needed to go into edit mode first to bring up the unwrapping.

I’m doing a tutorial here: Because the mesh buttons were being distorted by the armature in pose mode, he deletes the mesh buttons and texture paints new ones on the jacket. I can’t seem to do that. I can do it in the uv image editor, but it’s too hard to get them on the jacket correctly. I can texture paint in the 3d window only in multitexture mode. But those don’t show up in the render. Can someone tell me how to texture paint the buttons on the jacket in GLSL mode? Or if in multiresolution mode, so they come out in the render. He seems to do it in GLSL mode in the tutorial because I see colors. I was able to do this in an earlier step of the tutorial.

Blend file: