I can't believe it: I've downloaded the new version (Movement0510_b) and unziped it but for some reason I seemed to have opened main.c from the earlier script (Movement0510)

You are right, the mouse coordination is now o.k. Sorry, I don't know how I could have opened the wrong script.

I believe that simpler solution is a better solution, I wouldn't over-complicate features with slow motion features.

Btw, what about the design: do you think that we should keep the circle/knob position as it is now or move it at the middle of the screen & up or down? Are the circle/knob position dependent, can I redesign & move them without damaging the functionality?