Thanks! Just before I read your post, I had some luck using the remote keyboard on the original version too.
It would be very cool if you could explain how you got it to build. I tried, but Ant yelled at me.
I honestly lost track of who modified what. I don't think yours includes the down-buton-fix. Maybe we should move back to Github?
My guess about the login prompt is that the redraw/repaint methods on KindleTerminal do not get called. A workaround might be to just... call that somewhere, or just Thread.sleep for a bit. There is also some getText exception in my error logs. Maybe that's also causing trouble.
If I get it to build, I would like to add some sort of config file, so you cal tell it what to do at startup.