[sciurius]

I guess I have to cope with a basically unidirectional export to the Android device with MSP on it.

That is exactly what I have been doing from day one and what I would advise to everyone. A PC is much better suited to maintain/organise collections of music, and much less liable to get stolen, lost, or damaged. This is assuming you always make backups of the PC data -- which we all do, of course.

On the PC I have several folders, one for each musical project. Within these folders the music is prepared and eventually copied to the master tablet. I use rsync to copy but of course there are other means.

The master tablet is then synched (using library sync) to the cloud, and the other tablets are synched from the cloud.

My main problem now is that I didn't find the place on the Android tablet where snippets, that represent some work I have input in their definition, are stored so I can pull them back to the PC.

MSPro stores the annotation information in its database, and imposes this upon the document contents when displayed. So there is no 'modified snippet'. You can use the Print option to print to a PDF document.