There are a couple of things required to import (File->Place) a PDF of music from MuseScore, a free music notation editor from musescore.org.
Firstly, it is necessary to have the fonts used by MuseScore installed on your Mac. The important one for the music is Mscore text.
However, every musical symbol is displaced from where it should be on the stave. Their horizontal positions are correct but are sometimes higher or lower than they should be.
Each symbol is from the Mscore text font. The staves are represented as curves. It is possible that the curves are displaced rather than the symbols.
A sample file, Riley's Cow Shed sample 1 is attached, along with the MuseScore fonts. For lyric text etc, MuseScore uses FreeSerif.
The musical symbols that should have picked up the Mscore text font have been picked up by Lucida Grande. There does not seem to be a way of replacing Lucida Grande thoughout. The font manager shows it, but does not allow a substitution to be made. The text set in FreeSerif has also been substituted, but that is not as important.
I manually edited the first two lines of music to fix the incorrect font and change it to Mscore text.
Riley's Cow Shed sample 1.afpub