Hello,
You'd better contact support@realviz.com for these kind of issues.
We fixed some problems of stability (especially on the MAC version). Please check that you have the latest patch (http://www.realviz.com/downloads/patches/index.php), which is the build number 14039.
If it does not fix your problems, send to support@realviz.com your configuration (hardware) and we'll do what is needed to make it work.
Thanks