That eval version of Rhino 3 (and the full version, for that matter..) is not a very good example of how stable Rhino USED to be. Unfortunately, they released it before they should have. (guess they never heard about Curious Labs) You probably can't get yer mitts on an eval of Ver.2 any more, but if you can, try that so you'll know how good Ver.3 will hopefully become.