An application sends a ZGM_STOPWATCH_STOP message to get the elapsed time since the execution of the last ZGM_STOPWATCH_START message.
ZGM_STOPWATCH_STOP
wParam = 0; //not used; must be zero
lParam = 0; //not used; must be zero
This message returns the elapsed time since the internal stopwatch was started. The time is in 1000ths of a second. For example, a return value of 1500 = 1.5 seconds.