Why can't I play The Sims Castaway Stories ? The screen goes all black but I can stilll hear the sounds.

I bought The Sims Castaway Stories for my mac. My system meets all the requirements as listed on the software packaging. The system requirements are the same as for "Sims Life Stories" which runs perfectly fine on my computer. I have reinstalled the game 4 times. I was able to play it once, but after i saved & quit, the game wouldn't start up again. Is there anything I can do?