"they all do that, sir"

As previously mentioned, you need to add a little thickness to the take-up spool - a couple of turns of backing paper or similar is often enough. You will find differences between films too. I often just wind the arrows on past the start mark, to just by the take-up spool chamber. That seems to be enough to stop overlapping frames, though some are close.

The "red window", at least on the III, is not a red window at all, just a little spy hole - big enough to see you've got film loaded, not big enough to see the numbers.