Updated 12/30/18 Okay, so I have done my setup from scratch and I'm going to provide a step by step walk-through. I believe this is a good starting point for any new server owner looking to get up and running for the first time, or someone looking to play "Singleplayer" (Note: From my testing, the server needs to interact with Steam bi-directionally even for LAN/SP- some ISP's such as cellular hot-spots or NAT conditions may not work!). While this guide can be applied to all server types, t