I managed to build it, not in batch mode but opening the Unity editor. I think the issue was that there was no scene defined at all for the build settings.
Gameplay is somewhat quirky with the disconnect of panning the map view around using WASD keys an then setting a destination waypoint with a click. Especially when combat starts the screen should center on the ships in battle. It would probably easier to control if one had the mouse to set a destination point, with the map view following the mouse when it reaches the screen's edge...
Maybe it's already in there but I didn't know the key for it... having a "center map view on ship" button would be really useful...