Using VMware Fusion on Yosemite, how can I prevent crashes with sleep wake failure?

I am using VMware Fusion 7.1.0 on Mac OS 10.10.1 Yosemite. Every evening, I send my iMac to sleep. The next morning the mac usually sits in login mask - so it has rebooted. After login, I get "sleep wake failure".

How can I mitigate this? Are there any known workarounds?

I had this problem before with Mac OS 10.9 and VMware Fusion 6 but found no workaround. It seems, that with one of the updates of 10.9 the problem went away or was way more seldom.