If your Mac on forge is not shutting off beacuse you got the wrong verson of the mod or the wrong minecraft forge ver go to the back of your mac hold the of button for a few seconds it will say restart etc ignore that keep holding it then it will shut off then turn it back on w/ the power button on the back of the mac it will play the mac *ding* thing then wait it to load up do your password then minecraft will shut off (Hope This Works For You)