Do a nandroid backup!
Flash the device specific base ub_evitareul-ota-eng.rob.zip in recovery
Flash the "generic" quantal-preinstalled-phablet-armhf.zip in recovery. Get yourself a coffee 'cause this'll take a while.
Unplug USB if it's plugged
Reboot. You will boot to a black screen.
Open ADB and type the following commands
*Only if adb hangs. Do not issue this command if everything goes smoothly.
What Does Not Work?
Screen Brightness Controls
Internet Browser (No internet)
Sound (over speakers)
Audio Out via Headphones
Most Applications and Menus
Software Center (Note : You can install simple shell applications via apt-get install … once inside the chroot)
Most applications are placeholders
Auto Rotation (Or any rotation for that matter)
Notifications (All of them are placeholders)
Most Applications that do function are web apps like m.gmail.com.
Probably plenty of other stuff
Oppo find 5