When waiting for turn the and clicking on the minimized window a dialog box pops up asking if you want to unsubmit your turn and freezes stars. I've froze on other dialog boxes as well. however when waiting for a turn you just have to listen for the mac "BONK" then your new turn is ready and it is safe to click on the minimized window.
running crossover games mac 8.1.3
Macbook 2Ghz 2GB of ram 9400 256Mb VRAM