The improved_hud.7z file you have requested: Call of Pripyat / Mods / Improved HUD - 1.34mb is not available. Perhaps try browsing all files for the game S.T.A.L.K.E.R.: Call of Pripyat and upload any files you want to share or are missing. This is the only information we could locate:
The mod replaces the default HUD in the bottom right with a smaller, sleeker one. It also includes an option to remove the mini-map if you so choose.It has a very nice look to it.