Yay

Now my multiboot equipped device has a shell, too.
Big thanks to you two.

But another SOLVED problem hit me:
I am not able to get the blue arrow keys working (mainly '/' needed). Reaction is quite strange, for most keys just nothing happens, normal character appears. But for a few just nothing appears and for example for '#' and '*' it behaves as ctrl-m.
Do you have another hint how to enable full keyboard?

I have german layout and of course only english one would be available, thats fine to me.

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SOLVED
Hint was already given by reinob: look in recovery.sh
pali provided a kmap, which needs to be loaded via loadkmap (either given by pali or by bb-power).