are you using one of the preset applications? or using the New Form blank?
Are you using your own table? or have ing the preset create the table for you?
if using your own table, what is the table structure?
At what point does it crash? while setting up the pages? or while it is trying to create the pages?
If it is crashing while it is trying to create the pages, try closing the Files panel and the server behaviors panel if they are open before you start the wizard.
if it is crashing while setting up the application, try disabling the preview in the webassist preferences.