A tied pair of non-adjacent notes does not sustain correctly
In Musescore, ties function in such a way that a note can be tied to another, even separated by implied silence, as in the first staff in the above image. This isn't unprecedented, and the behavior should be allowed. It appears for instance in the Alfred Essential Dictionary of Musical Notation on page 325 as in the image below.
However, the playback which Musescore uses in this situation doesn't produce the desired effect of sustaining the note through the end of the note it's tied to (the equivalent traditional notation for which, and the one which generates the desired playback, is included on staff 2). Instead, the ending of each note is staggered in relation to the duration of the tied note + the duration of the note to which it is tied. This behavior corresponds with voice 3.
To reproduce this issue more clearly,
1) Simply enter a series of, for example, four eighth notes.
2) Enter a chord, in this example an eighth-note consisting only of all of the notes in that series.
3) Select the eighth notes and use the tie command, which will couple each note a one in the chord.
4) Observe that in playback, the releases of these notes (as indicated by blue highlight) are staggered, and because the duration picked for the chord is short, the first few notes terminate before reaching beat 2. Experiment with the duration of the chord, and you should find that each note is extended by the duration of the chord, but they do not terminate together. As above, rather than staggering, I expect all of the notes to terminate with the latest one.
A potential application of this, aside from measured arpeggios is sustaining notes on specific strings of a guitar as in the attached example, where the playback doesn't last the expected duration.