MuseScore won't import properly from music XML files with no staff names
The attached xml files (guitar staff/Tab) were created with Finale 2009. The only difference is that in one the staff labels were hidden on export to xml; in the other the staff labels were visible.
The "aguado_unlabelled" MusicXML file (no lines labelled) imports only the Title, Composer etc. – no music staffs at all!
The "aguado_labelled" XML (all lines labelled) imports everything correctly.
Note that even if one of the staffs is labelled and the other is not, import will still fail for all lines.
MuseScore should be able to import all staffs even if they have been exported by the parent program with no staff labels.