So I got the obsidian gate opened (from the - guess! - east). When walking in from the north through the now open north side of the area, I got told - again - that the gate is closed, although this time I did manage to walk through.
The ship is nice but strange... it doesn't go everywhere I want it to go, and even the path it was supposed to take was weird, where I could only navigate it one tile at a time.
It was also incapable to go far NE from its home port.
My city at the very east grew big enough - I teleported over the river. And assume that I found the area where Part II will be, once it comes out - big barren empty area...
Ciao,
Klaus