WOA! That's of course the right / correct answer to my problem as a whole. Thanks a lot! I originally only wanted to move parts so the whole piece will fit on a single page, which I managed > as per Billy's steps (and some more). But i'm dying to hear the midi version as well :) It's harder to find "score ocr" for linux, but the thing isn't complicated for (re)writing with lilypond etc.

is there a way to move ALL layers into a group, instead of dragging manually, one-by-one, 100+ layers?

@stan - Hebrew is exactly like English in this respect: It has a bottom baseline. and like other latins, some letters are taller (לf), some go down (קךgy).