The mod is for Shadow of Chernobyl version 1.0006. The "Return of Scar patched.7z" file has all the cumulative patches and fixes for the mod already applied (up to cumulative patch 3 and a few later fixes from the Russian community). Install it first by copying over the bin and gamedata folders to your ShoC install directory. Then install Stalkerstein and Grunter Hunter's excellent translation from the "RoS English v1 by SS and GH small.7z" file by copying over the gamedate folder and merging it with the one you just installed. The "Return of Scar guide.pdf" file is a translation of a Russian guide by, I believe, Grunter Hunter. The orginal Russian guide may be found in the gamedata\!!README!! folder along with other helpful guides. Have fun!