Hey there Captain Assburgers,

I think the reason you can only play on a local server is because there aren't currently any (known) dedicated servers for this mutation. Dedicated servers for specific mutations tend to be quite rare unless the mutation is REALLY popular. So to play with friends over the internet you will have to host locally. I suggest the person with the fastest internet hosts the game.

I'm not sure what might be causing the error messages. I suggest all making sure L4D2 is up to date and that you launch it from the steam games menu without commands. Once that's working then make sure you install Old School by subscribing here. Next follow the tutorials in the other discussions. If it's still not working after all that then leave a comment here with more descriptions of the errors and I'll look into it further :)

Cheers!

well we found out what we had to do, to play a multiplayer match it has to be local and you have to join the game through the join game option from the drop down menu when you select the host on your friends list, however this must be done after the game has started as starting the game with people in the lobby causes it not to work crashing and/or freezing the game.

Other than that it works fine, great work on the mod me and my friends love it.