C_b_fofep and I decided to convert the Alien Swarm build back into an FPS source engine version. This takes the orange box or the SDK template code and dunks it inside the Alien Swarm engine.
The files you need for SourceMods directory in order to make your game use the ASDK source code. This basically is Alpha because it's ripped directly from my studio's game files and we no longer use Source. So any references of "The Somme" is us! Don't worry, just replace it with yours. I unfortunately don't have time to document the entire conversion but hopefully someone can make a cleaner version of this in the future.