You want an early peek? Look here.
I added a function to disable UltraXP for all users. Not just you, but everyone who views the project. Think about that for a sec. Any ho-hum user who read this blog and has a Scratch Beta account has supreme domination over UltraXP 2.0. Also take care to note, however, that I (nobody else, yet) can reverse this course of action. If you want to disable UltraXP 2.0, you could, but you must have a reason for doing so. Don't tell me that your cat walked all over the keyboard and happened to tap Enter. You can only legally disable UltraXP 2.0 if it's because the OS has a bug. If and when you do disable the OS, you are obliged to use the comments field below the project in the project page to report this incident. If you do not, I will program UltraXP 2.0 to automatically ignore your command to disable the OS.
Anyway, if you've read the above and you still want to disable UltraXP 2.0, enter the following command into the command line under StartScreen -> Settings:
sudo "/system #config -disableOS?code=(446464645646461263556464)
Then you will be redirected to the failure message. You cannot reset this state once you have entered into it.