I did initiate all that and went to the spring, not the lake with the root
after accepting as a devout and then after the next options, nothing happened. I checked the hot spring and nothing changed.
So I'm not sure if it just hasn't been implemented yet or if it is a bug
Viewing post in Question for future development.
Ahhhh, the hot spring upgrade for the shrine isn't actually available yet for this version, my apologies! (I was thinking about the most recent build for the patreon for this one). If you have Velani accessible via the devout list, then you should be good to go, and the hot spring upgrade will happen automatically once the build with it is live!