[lllboredlll]

Is Seven a part of your customization?

If so, aslong as you don't have a registry addition error (which that don't look like it has) it won't hang up the customizations because none of those keys are active until you reboot or even some not until you run a command. A bad key that was accepted could however hand up the next boot cycle. What I've experienced with all the flashes I've done lately is that if your customization process has a bad file or command it will hang. My example would be when automating my gps fix process, I failed to get a file to copy to windows. There was a final command to launch that file in the last customization process before lock and reset. Needless to say things didn't go well.