Song arrange versions (musescore, songbook)

Hello all.

The function PARTS allows to make singular parts of the score or groups of parts. Now I am making a songbook for pupils of highest classes of basic school. There shall be rich instrumentation of Orfs instrumnets so that children can use them tastefully. There can be allso instruments that some children commonly learn in music schools.

Publisher (working for ministry of education as a contract authority) supposes, that all the music will be in electonic form and teachers and pupils could switch between versions of arrange. The versions have to be "Voice with piano" (obligat), "fully arranged version" (sometimes without piano), singular parts and maybe some else version.

I have an idea, that these versions could be the groups of parts, if in application songbook would be possible switch betveen one version (one group of instruments) to another. I wanted allso ask to make mutting (on mixpult) independent betveen the versions, but I found, it allready works.

There is one little problem. Frames are not independent, so if I want to write special comments for each instrument, I must use so many frames, as is number of versions and make in each version invisible other texts and frames make zero dimension. This way generate pretty mess difficult for editing.

GIT commit: 3543170