Bitfields for mouse call mask:
Bit(s)	Description	)
 0	call if mouse moves
 1	call if left button pressed
 2	call if left button released
 3	call if right button pressed
 4	call if right button released
 5	call if shift button pressed during event
 6	call if ctrl key pressed during event
 7	call if alt key pressed during event
Note:	at least one of 5-7 must be set