The easier way is simply download another mac game (or the previous mac version of this game), then download the window version, open both (for mac, right click the app & choose "show package contents"), delete everything in the app.nw folder in the resource folder of the mac version, then copy or move everything from the www folder from the window version to the mac version, then open terminal, use the chmod +x command on the app & it should be good to go. It'll crash a few times (so saves often) on launch, but will be running normally afterwards.
This method will save you from booting up an actual server just to play a game.