This is a general guide on how to get any mod of your choice working on Aliens vs. Predator 2
It could be anything from a skin pack, a sound pack, or a texture pack
Most mods will come packaged as either a .zip file, .rar file, or .7z file. You will need to unpack them with any file archive program of your choice. WinRAR or 7-Zip are the preferred choices from AVP2.org.
For this example we will use the High Quality Pack 2.0 - High Resolution Textures pack.
Unpack the mod
After extraction you will see a .REZ file (Some mods such as UMP2 are stored in a simple folder, in this case, treat the folder itself as just a .REZ file)
In this instance it is called rgsnd3.rez.
Move the .REZ file into your main AVP2 directory, wherever you asked the game installer to install to (Default is C:\Program Files (x86)\Fox\Aliens vs. Predator 2)
Once the .REZ file is in place, open the AVP2 game launcher (AVP2.exe), Click Options. You will see a black command line in the window. This is where you will tell the game to load the mod. The proper syntax for loading any mod goes like this:
In this instance we will type this:
Also make sure to click the box labeled Always specify these command-line parameters so you don't have to re-type the command every time you launch the game. If loading more than one mod at a time, just leave a space between the previous entry, and start the next entry with -rez, for example:
Click OK and then Play
Your downloaded mod is now properly installed with the game.