It seems to me, the more you save the scene and do test renders a number of times, then, bang, it will no longer save anymore.  I was working on the problem files for about an hour before it started crashing.  

I have also seen problems where it renders fine, then the next time you render, it comes out all black (at least it was very quick). The only way to get back to normal renders was to exit Vue and restart.  The it would render a few more times before going back to black. 

I put in a support ticket too.  Thankfully, none of these files are critical work stuff - just playing around. 

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