Ill probably be re-releasing this again, as a public server, instead of private, it just makes things easier, and allows more people to play with you, we don't always get HGNERS on there sadly (at least 4/4) at the same time.
The issue with L4D is how many people can play, perhaps make it a versus gamemode so more can be in the server?
**Points at SK**
I invited him thousands of times and he always said "GTFO!"!!!!
There's a mod that allows I think 16 players, there will be dupes of the charecters respectively though.