1. Make a backup of the files mentioned below of the original RtCW game, 
because they will be substituted:
	a) cgamex86.dll
	b) qagamex86.dll

2. Unzip all files to RtCW directory
3. Play the addon with shortcut "Iron Cross.lnk"
4. After you finish the addon, replace the "files.dll" in your original game.

Note:
The shortcut only will work if the game be installed in C:\, except you it should change the properties of the shortcut indicating the new way.