My brother's game won't activate in his Macbook Pro 13" (Mid 2010). We were given a lot of keys to be able to activate his game but no luck. But when I tried it on my Macbook Pro 13" (Mid 2009), it worked. His OS is HDS ACYLeopard 10.6.8. Also, it's dual boot. So I was wondering, is it because of the dual boot? Also, is HDS ACYLeopard 10.6.8 a valid Operating System?