just in case you are still looking for a solution to this, the workaround is to download xquartz (http://xquartz.macosforge.org/landing/) and run it every time before starting crossover. works perfectly for me
Anyone found a solution to this? I found that other Bottles such as Office 2007 are crashing as well. I tried to xquartz workaround mentioned above it failed to have any effect. It also seems that Crossover is not able to enter app nap as per Activity Monitor.