It seems that what you are saying is that if you move enough windows from their default location in the middle of the screen, then it starts to reset some of them. It makes sense there is some sort of limit but it looks like it is a very large limit that most people would not achieve because the default location is fine. The limit is most likely at least 64 given the amount of steps you provided.

I don't see how resetting temporary windows would affect permanent UI Elements such as job gauges in the HUD Layout, but since you can save the HUD Layout you could load a different HUD Layout then reload the original one to get the position back.

I've had the same HUD Layout since I began playing in 2015 which I have copied over to new computers over time and it hasn't reset yet. I think some of it did reset because of a crash once but I had a backup.