HandMorph is only drawn when its carrying another morph. What you see in the screen is the "hardware cursor", maintained by the vm.
This separation was done for efficiency reasons, when drawing Morphic.
This is why you evaluate stuff like Cursor wait showWhile:[], to alter the appearance of the "hand/cursor", instead of changing the HandMorph directly.
So what you are doing by sending the message above is simply positioning a hidden morph, the hand, at a 10@10.
Maybe, try to see if you can position programmatically the Cursor instead.
Saludos,
Fernando