For the mac version people at daz know about all problems and are running to fix, just keep your eyes in the bug track. Servo, if they cant reproduce the problem is hard to fix. me major problem with Windows are the UAC that crash a lot Carrara and other softwares... try to find a possible reason, so tehy can investigate. I had a problem with the Plant Editor, but they couldnt reproduce, after send a video showing what I was doing they found the bug and fixed. Without any information, just saying that it crash at startup dont say nothing.
There a lot of system routines in Win7 that can be turned off. Post more about the problem, maybe some software are blocking Carrara.

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