@DiapDealer: Ooh, you're right. It's carrying over the offset from the mobi7 part!
And I was wrong, AFAICT, the few KF8 files I've checked (straight from Amazon) only keep the correct one, so, yeah, maybe it gets 'fixed' after the KDP pass...
That would imply that the 'split' action of MU should do the same
That said, I'll check how my Touch handles those master mobi, see if there's really an issue on the K3, even if what KG does isn't terribly smart in the first place.
I'll try to come up with a less broken MU patch after checking all that
EDIT: FW 3.4 bug. It's working as intended on the Touch. Weeeee... -_-". Add that to the weird can't change font families bug in some KF8 files that uses multiple families for styling ... (Another thing happening on 3.4 that works flawlessly on the Touch).