I am having a hell of a time with 2010 FloWorks. For some reason, I can't get passed the wizard set up. I just about get through the wizard set up and I go to save/ exit the wizard and SolidWorks as a whole crashes. This has happened each time as I have tried and retried the simulation. I even went as far as re-creating the whole assembly because I wasn't sure if there was some type of glitch with my original assembly.
Impossible to diagnose without seeing your model. If it's reproducible, create a Rx file and send to your VAR. It may be a bug. It may be install related. Regardless, there is no legitimate reason for this. Best to get someone to take a look and confirm the behavior on another system.