Hey guys, we're working on it. As for now all I can say is that You should try to update your graphic card's drivers to the latest NVIDIA version. Most of the problems we've encountered on linux versions were caused by the drivers.
(Which You can get from the official NVIDIA's site:
http://www.nvidia.com/Download/index.aspx?lang=en-us )
Also, we would like to remind all of You that we officially do not support linux distributions other than Ubuntu.
Sorry if that's not enough but we're still working on it, yet we all have our limits and our resources are not infinite unfortunately. If update won't fix any of your problems, keep in mind You can always contact Steam directly to get a refund.