Installing:
Move the content of the archive to the root folder of the game.
For example: “C:\Program Files (x86)\Steam\steamapps\common\FEAR Ultimate Shooter Edition”.

Information for new ones:

How is mod loaded?
Two simple steps:
1. Add your mod file (.Arch00) to root directory of game
2. Add name of file in the end line of Default.archcfg (it places in the same root)