I think trying to debug Tk is very unlikely to result in success for your application.
If you exceed some Tk limit and that causes some error, then try another way.
Finding and fixing some Tk bug is a very last resort.
Please explain why my code at Marshall's TableMatrix code is not a sufficient example which can be adapted to your needs?
That explanation would help all of us Monks understand what you are trying to do. At this point, I don't think any of us are sure.
GUI code can be very, very tricky to write. And a lot of experimentation is usually required.