Plugin Installation help

Hi,

Im trying to install the Saxophone Fingering plugin (https://musescore.org/en/project/saxfingering) but cant seem to figure out how. Ive tried following the handbook part that mentions this, but it says something about some plugins needing fonts, which i think this does, and cant find any way to install new font types. All the pre-downloaded plugins seem to be in .qml files, which this isnt. Can anyone guide me through this?