Here is my thought, the default color of a mesh is white and you colored the copied mesh as black, then relocated it on the z axis, when you flipped it maybe the color was lost because it is now on the inside, and the inside is white.
Eh? Nonsense.
@ Kip, is this what you want?
out = CopyMesh(ball,ball) EntityColor out,0,0,0 FlipMesh out UpdateNormals out ScaleMesh out, 1.1,1.1,1.1