I plan on writing some instructions on how to launch and configure a server for all the different OS's since the only instructions I can find through google-fu are Steam specific at this point. I have only just installed the game on Linux and Mac, but I plan on adding windows in the future once i get to it. Linux is also a work in progress at the moment.

If anyone beats me to posting the steps for an OS, I'll put them in this main post to keep the instructions at the top of the thread.

********* Windows Instructions ********

********* Mac Instructions ********

Note - This assumes that you installed the game in the default location of /Applications. If you installed somewhere else, change your paths accordingly.

1. First, click the 'go' menu in the finder and select the 'Utilities' item. find the 'Terminal' application and double click it to open a terminal. you'll use this later.

2. go to the 'go' menu a second time and select the 'go to folder...' item (or hit cmd+shift+g) and paste the following text in the window without the quotes:
'/Applications/Project Zomboid.app/Contents/Resources/game'
and click the 'go' button

3. In this folder, go inside the PZServerSettings folder and locate the PZServerSettings.sh file. Drag and dorp this into the terminal. It should paste the path to the file into the terminal. Hit inter to launch the server configuration tool.

4. Modify the server settings to your liking (you can read the steam documentation to find out what all this is if it doesn't make sense to you). Then save the files and quit the program.

5. Back in the finder window, go back to the folder we opened in step 2 and drag and drop the StartServer.command file into the terminal. Press enter to start the server. You will be prompted to enter an admin password. This creates an 'admin' user with the password you specified. Eventually you should see a message about the 'server is listening on port xxxx' (16261 if you left it the default). You can now launch project zomboid and connect to the server using that port and the IP address of 127.0.0.1 (if you are running on the same machine as the server).

NOTE: you can run all the admin commands from the server terminal. Don't use the preceeding slash that appears in all the documentation for executing commands. You can grant your account admin privileges to use those same commands in game.

********* Linux Instructions ********
Note: this assumes that you installed Project Zomboid in the default location of '~/GOG Games/Project Zomboid' If you did not install in this location, adjust your path accordingly.

1. Open a terminal and enter the following command:
~/GOG\ Games/Project\ Zomboid/game/PZServerSettings/PZServerSettings.sh
This will launch the configuration tool. Configure the server as you like, then click save and quit.

2. To start the server enter the following command:
~/GOG\ Games/Project\ Zomboid/game/projectzomboid/start-server.sh
If you get an error about not being able to detect whether java is 32 bit or 64 bit, try cd-ing to the directory containing the start-server.sh file first.
cd ~/GOG\ Games/Project\ Zomboid/game/projectzomboid
./start-server.sh

That should launch the server. You will be prompted to enter an admin password. This creates an 'admin' user with the password you specified. Eventually you should see a message about the 'server is listening on port xxxx' (16261 if you left it the default). You can now launch project zomboid and connect to the server using that port and the IP address of 127.0.0.1 (if you are running on the same machine as the server).