So... thats a lot of words, I think your only concern/question is that you are trying to get the ZAC36 firmware updated? Sounds like you think it updated but it is not showing 1.21 on the device page?
Did you install the Advanced driver, which is actually this driver (by me): [DRIVER] Zooz ZAC36 Titan Water Valve Actuator
Once that is on there and selected for the device, if you run a configure it will query and update the firmware version shown at the bottom of the device page. You can turn on debug logging to very and see the response from the device (in the logs).
I will also be working on a couple of fixes for this driver this weekend hopefully. Mainly, Zooz let me know they missed some battery pack related settings in the docs which I will add. It still works without them you just cannot adjust the battery reporting settings.
