I used the guide from Chuwi site which is very much similar to the one posted in the Forum.
Apparently, my two tablets belongs to the super early batch 00241 and 00253 which they said upgrade only when needed, which I did so and thank goodness I only upgraded one with such issue.
I have the same problem now with my tablet a V200 version, first batch as well! When i connect it to an external monitor, the external monitor works just fine, but the screen of the tablet is still flickering / flashing. Have you fix the issue? What’s the status of the tablet.