Did you try re-installing the old unofficial v0.18 ROM you linked to in your earlier post? If you can do so, and enable rooted debugging, you could back up your apps and data using either of the two methods mentioned in this post. (Even better, try both methods, in case restoring from TWRP doesn’t work)
It may not work, but ot gives you a chance of still having your apps and data after the update?