I just had the game freeze when zooming out. I took a screen shot, ran SDSupportTool, and opened a ticket. Other things I noticed are that the game still seemed to be running, just not updating the window. The music kept playing, the CPU Usage meters showed usage consistent with the game still running, etc. When I minimized the window (I play in windowed mode, primarily to keep my resource monitors in view) and restored it, it came back up all black (it didn't refresh the window). I was not able to close the game window by using the "close" button at the top right corner of the window (the "X"), but I was able to close the game from the task bar (another reason for running windowed).