I've been asking some friends and received this reply:
"Clive,
I have several copies of windows ME, including full versions and an upgrade version. The 'regenv32.exe' is in the win17 cab file and they are all 60kb. Where does the 72k version come from. Sorry I couldn't help with a 72k version."
I'll give him some background information and see if his CD's are originals or backups.