Below is a list of the different possible endings to the game. If you want to be sure to get the correct Wishgranter ending make sure that not more than one criteria has been fulfilled.

Unlock Ending A:
Go to the Wishgranter with at least 50,000 RU.

Unlock Ending B:
Go to the Wishgranter with over 1,000 Rank Points.

Unlock Ending C:
Go to the Wishgranter when Lukash and Voronin are both dead.

Unlock Ending D:
Go to the Wishgranter with less than -1,000 Rank Points.

Unlock Ending E:
Go to the Wishgranter without any of the above criteria.

Unlock Ending F:
Join the C-Consciousness.

Unlock Ending G:
Refuse to join the C-Consciousness.

To get into the armory without being detected push a chair towards the guard. Don't worry if the chair falls down partway. When it touches the guard jump on it and then jump onto him. The game will then push you past the guard and into the armory hallway. To get in just slash the lock with your knife and to get out use the same technique you got in using a chair which is in the armory or the other room.

At the main S.T.A.L.K.E.R. Directory go to 'Setup-bp' and enter the following passwords without the quotes to unlock the corresponding effect. These two codes are exclusive to the Limited Edition of S.T.A.L.K.E.R.

Unlock French and German Military Multiplayer Skins and Multiplayer Map - Dark Valley:
Enter 'snork'.

Unlock UK and US Military Multiplayer Skins and Multiplayer Map - Pool:
Enter 'pseudodog'.