I thought I posted here about Firefox crashing on me, but maybe I didn't. After a few days with WZ not loading at startup, and not running in processes in Task Manager, the crashes are no worse or better. I'm no longer see WZ as a prime suspect, and whatever problem it is, it runs deep as FF will still crash in safe mode.
Have you updated to the released build on the website? Please uninstall your current version, reboot, and install from WindowZones.com and let me know if the problem continues.