That should work. So how is your mesh different from the cube? Did you paintmesh the cube with a surface brush from your mesh and then paintentity it with the meshes entity brush? You need to compare like for like.
In short you could being doing all sorts of wierd and wonderful things to your mesh, which you have not told us about :)
In short you could being doing all sorts of wierd and wonderful things to your mesh, which you have not told us about :)