my post about the power-off screen was a false hope, I only managed to get the hardware button to work once, now it's back to the frozen homescreen, but I can always power off from the KoReader, then it works
here's another nut to crack, a huge OCR'd pdf that has all the footnotes in the margin. Reflow text / two column mode messed it up, I only just managed to read on my 7,8" reader in non-reflow landscape mode