Well that was exactly the point. Information is not just for computers - a “0” imparts no information to a human other than inferring the computer needed it for some internal reason. An actual track number implies (potentially incorrect) information about the running order of the music to both the computer and a human.
This does appear to be the case. Just moving a folder or renaming the tracks is not enough - the whole Plex Dance (move, scan, empty trash, move, scan) needs to be employed which is a real pain when you (read: “I”) have over 100,000 tracks. I also need to find a way to do it which is compatible with my non-Plex music management set-up.
Thanks for your time today and if I can offer any more information from my set-up which will help, let me know.