Left 4 Dead 2 is an awesome game and I wanted to master the Source Engine. So I created my own Left 4 Dead Campaign called 25 to Life! I am very proud of how it has turned out and how well it has been received by the Left 4 Dead community.
Instructions after the break.
How to install maps and addons (.VPK)
Installing and playing custom Left 4 Dead 2 maps is very easy and can be completed in seconds.
2. Extract and open the .VPK file.
* A confirmation box will appear letting you know the Add-on has been installed. (see below)
* Manual Installation:
Place the .vpk file into your L4D addons folder.
C:Program Files (x86)Steamsteamappscommonleft 4 dead 2left4dead2addons
How to Play Custom Maps in Multiplayer (.VPK)
1. Players must download and install the .VPK file.
2. Create a lobby as a ‘Add-on Campaign / Map’ and start the game!
3. Your friends must have the same maps (and version) installed in order for you to play them multiplayer.