From Luthiers post:
Extract the contents to your
[Program Files]\Steam\steamapps\common\il-2 sturmovik cliffs of dover\

be sure to install hotfix also....

you dont need to change anything in steam, prior to updating the game (but defrag your cache files from time to time regardless of patches - right click on game in steam - local files - defrag cache game files)

heres the link for patch and hotfix:

http://forum.1cpublishing.eu/showthread.php?t=26761

Why would you revert? The official patch is coming...