I am seeing a problem with changing colors on some objects. The color stops changing after two or three times. I noticed it's happening, not always, when the source file has a shape on top of another shape. Does this transfer over to the png in layers? Would this cause the issue?
I don't know exactly what you mean. If you are just coloring one bitmap, I think it only colors one bitmap. A shape on top can certainly block the mouse - try a noMouse() on it.