Patch problem: No version of MOW installed?!

[MiKye200]

Well, I botched something up trying to patch MOW after purchasing and downloading 1.11.3 off Steam(why is Steam dowloading an old version, anyway?).
After following a link to the 1.16.4 patch I downloaded it, backed up my MOW folder and ran the patch, copying the resulting files directly into the Steam MOW folder.
After firing up the game the welcome screen of MOW still showed 1.11.3 but when I went into multiplayer a Japanese army was possible, so apparently it patched OK(still odd though that the 1.16.4 patch did not show on opening screen).
Anyway, when I exited the multiplayer screen I received a message that the program had stopped working.

Uh Oh, I thought.

So I copied the backup Men of War folder back to the original.
Then, after further reading on the forums I notice that the 1.17.5 patch is out, so I download that and try to run it, only to get the message that the patch cannot run because it does not detect that MOW is installed,

"The setup has detected that no version of Men of War is installed"
"Setup cannot continue",
or words to that effect.

Well, that's odd, because it still runs when I click on the desktop icon.
Damn.
So, by copying the backup MOW folder over the patched MOW folder did I do something to the program registry; is that why the 1.17.5 patch cannot detect a MOW program installed?
Just what is the patch checking that it cannot detect the program?

So, if I do need to reinstall MOW, where is the install program that originally downloaded from Steam?
Please don't tell me that I need to download it all over again; my ISP download limit is approaching maximum for this month.