I downloaded Mythruna, loved it! My brother saw me playing it, downloaded it and loved it! We immediately wanted to play on the same world together so I thought I'd try be a good sibling and would attempt to set up a server so my brother and I can work together. However this was easier said than done

Downloaded the Mac stand alone server, double-click it - nothing happens.
If I show package contents (open it) and double click the Mythruna-server.jar, the interface appears so I can name server and port number. If I then click save and run,
a box appears for a second then disappears. Im not able to log in to the server I just created and named, as the game just freezes on the Multiplayer screen. It doesnt get to the enter username part, so I assume I have done something wrong. Now I will stop here and say I have no real idea what I am doing..... which I am sure is pretty obvious

Looking on the wiki, I found the information on the previous way of setting up a server (linux version) but nothing on the newer stand alone way. It appears you can just double-click the standalone server to start the interface but it does not seem to be doing anything, unless i specifically open the .jar file located inside.
Any help would be appreciated,
Thanks
Rennie