yes, i already tried that. i tried the following variants: boot into android and then backup&restore, with that the box boots directly into the android recovery and gets stuck there with the error message from above.
the second variant, as you suggested: with a toothpick in av until the nexbox logo is gone and then released, boot into android recovery again and again cannot load volume /misc.
it just doesn't work :-)
i have tested several dtb, changed ini-files and everything else, but no chance.
maybe i should try it with a SD card, is it USB?