The improved_icons.zip file you have requested: Shadow of Chernobyl / Utilities / IMPROVED ICONS FOR S.O.C. & C.S - 117.66kb is not available. Perhaps try browsing all files for the game S.T.A.L.K.E.R. Shadow of Chernobyl and upload any files you want to share or are missing. This is the only information we could locate:
This is a modders resource for anyone who wishes to use these improved icons in their mod. Please see the readme for further details.