Ctrl+N and F1 shortcuts broken
This is a sequel to #7 (closed). The F1 keyboard shortcut broke in c0d063bd. It should be removed from klotski.ui and go into Klotski.startup() I guess.
Then I suppose Ctrl+N was probably not previously intended to work, but it would be a bit weird for Klotski to be the only game where it doesn't start a new game. I would make it perform as Start Over.