i was running 3.11 but im not sure if that was the problem, i had a friend take a look at it and i think he posted the code as a branch off your post
Seems like the order of arguments to BooleanVar must have changed at some point, or something… For now, I’ve made a minor change to the code to try to maintain compatibility with more recent versions of Python and Tkinter. (The most recent fork also does a slightly different method of the same idea.)
Let me know if there are still issues, since I’ve not tested the changes extensively yet.