Downloaded the file our friend @nandfhz
managed to get from a seller and these are the results:
This is a older version of ZUI: 14.0.413
Since this an older version, it's not recommended to use it so no need to share a public link.
After flashing this older ZUI version, I had to factory reset via recovery mode. Then it booted just fine. After setting the tablet I was surprised with an update notification. (no VPN no nothing). It just offered me to update to ZUI 14.0.640 ST.
The update was 252.02 MB and took a lot of time to finish.
After rebooting I got another update notification, again no VPN. This time offering me to update to ZUI 14.0.691 ST. 195.87 MB update. After this update I had no new update notifications. This should be the lastest available update so far.
This is the same version we got from Lenovo service tool.
List of ZUI versions for our tablets so far:
ZUI 14.0.413 - Possibly the very first release or one of the firsts.
ZUI 14.0.640 - Initial update with minor fixes.
ZUI 14.0.691 - Possibly the second update with minor fixes. This is the latest available update. Confirmed.
No VPN seems to be required to get Updates. We just need to be patient. We all should get a notification once a new version is available. Will update here otherwise.