oops didn't notice this before - can't remember if it matters or not... you don't want a space between If and WinExist - "IfWinExist, ahk_id%id%" is what I do.
Another thing, sometimes controlclick isn't so good at the clicking, and this works more reliably (if the control accepts keyboard input properly):
Code:
ControlFocus, Button63, ahk_id%id%
ControlSend, Button63, {SPACE}, ahk_id%id%
Seems fairly random to me which is best for a particular site.