I have read that certain tuplets can spook XML conversions to the extent that everything that follows is a complete absence of notes. I can certainly attest to that. This passage (shown here as a screenshot from the piano part of the Sibelius original)
is a line that XML won’t cross, and I can’t figure out why. Here’s what happens when it’s imported into Dorico (not a single note survives after the car-crash bar; I’ve kept in one orchestral staff to show the rests) :
I’ve already done two more downloads, creating progressively more empty bars where the notes were, but I can see nothing that would unduly bother any conversion algorithm. They are standard tuplets, no nesting; there are no mismatched bars (i.e. apparent beats vs time signatures); there are no hidden or deleted rests. I could of course delete all the notes in this passage and reinput them in Dorico, but it would be useful to know what the no-no factor in material such as this might be.