Thanks Monterey this is EXACTLY what I was looking for and thanks for talking me through the mistake I made.
This is a brilliant little utuility, the way I do it is I have 2 versions of game 4.08 on one drive and 4.09 on another.
I extracted the utility(very simple to do) into my 4.09 game and now I can sitch between versions on the 4.09 game only(I use the 4.08 for online HL etc).
However if I change the path in HL to my 4.09 game it makes it EASY to switch back and forth for online games using my 4.09 version ONLY indeed I could easily just delete my stock 4.08 on my E drive although I want to keep it "just in case"
