Not to interfere with fixing the issues for classical users, but this caught my attention,
because I always wondered (and complained) about the inability for users to fix the common issue of tracks not having the composition property for unknown reasons - and hence not being included in the list of performances. Maybe this is related to the same fundamental issues.
This is quite common and affects both classical and non-classical. It would be awesome if you could have this on the radar as well. You may have seen it, I have summarized what I and others (shout out to @tripleCrotchet) managed to find out about it in this thread, and the various other threads linked from the posts there: