A side question here - if we've modded some files (and, naturally, saved all the originals) do we need to change the game files back again before we update with the patch, or will the patch just replace everything?
I would put the original files back, or better make a separate desktop folder copy of the game to do all your modding with, this way you'll always have a permanent "official" version on your C drive, and then a modding playground to play off of on your desktop which you can tweak to your heart's content.
When a new patch comes out, just save copies of the files you edited in your desktop folder, junk the desktop folder, make a new one with the contents of the newly patched base game, and then after you play the new patch for a while, see what modifications that you made from before are still needed in your desktop mod copy version.