I also have seen various HVT issues. Before I did that though, I would try checking the driver checkbox "Print Text As Black". That may improve your...
ID & Print, is where you set up an account for each user, they have a user name & password, which is entered into the print driver, once, and saved....
How long is a piece of string?.... more info is needed, unfortunately, even though some of "us" are good....however, "we" aren't good at guessing.......
Never installed KM 5020i but brand new Brother originals don't ask for Time zone for sure, time is set via Initial Setup. Should Factory reset don't...