Crashing a computer/software program can be caused by a number of different factors. The primary question when evaluating this is whether the crash is random or if it can be duplicated.
Random crashing in GibbsCAM is nearly always a result of the video card and driver. This video card technical article provides specific information about recommended video cards and where to download current drivers.
If your crash can be duplicated then there may be a problem with the model or with the software. Please e-mail the file to firstname.lastname@example.org with a brief description explaining how to recreate the crash.