1. Got to your main install directory
2. Run file called setup-bp.exe
3. Choose your install language
4. Enter these BONUS UNLOCKER CODES:
pseudodog = Unlock code #1
snork = Unlock code #2
5. Press NEXT button and you got the BONUS content unlocked download the file: stalkerbonus.zip
(to unpack archives use: WinZip,WinAce, WinRar)