during our tests, we found out, that "disable graphics card" (photoshop>settings>performance) in the mac pro from 2006, would prevent a crash, when using "refine edge".
Have you tried »Basic« or others under »Advanced Settings«?
What are the other Performance Preferences?
What have you done for general trouble-shooting yet (trashing prefs, system maintenance, …)?
With the latest dot releases, we've found that the majority of the crashes are due to third party plugin bugs, and some OS bugs.
Without a crash report to examine, we can't tell exactly why you're crashing -- but you should try disabling third party plugins.
it could be the gpu of the 2 mac pros (shipped ones), as disabling them under preferences (disable "open gl") prevents the crashes, i had no crash since the disable method.
nevertheless i sold my other mac pro, i am buying the latest " iMac 27" i7 2013 " now with 32GB RAM.
we will also sell the 2 mac pros and buy the latest mac pro 2013 (still unreleased), with AMD FirePro W9000
Instructions for submitting crash reports with your email address: http://adobe.ly/gNJWVY
As Chris states, this will help us track down your issue.
I agree is Christoph, I would suggest leaving OpenGL/"Use Graphics Processor" enabled and twiddling the Advanced settings for Drawing Mode to "Basic." Then restart Photoshop and see if the problem still persists.
That setting is the main difference between CS5 (Basic) and CS6 (Advanced).
i had crashes in "gpu: drawing mode "basic", too. but we will sell all old mac pros from 2006-2012 and buy the latest mac pros 2013 in december with "AMD fire pro w9000" gpu.
so problem is gone, thanks!