If an asset isn't used on stage (for instance, popups that you add to the program with getDefinitionByName/addChild), it seems that the AuthorTimeSharedAssets doesn't always update properly. Is there a way to manually update the link?
FWIW, if you go into the Symbol properties and uncheck "update automatically," then go back to the library and check the "link" box, this usually forces an update (and even allows you to say whether the shared or local symbol takes precedence).
It also seems my issue wasn't that the assets weren't used on stage, it was that each xfl has its own subfolder (which is a bow to how FB expects you to structure a workspace when you're pointing to a Flash project).
Europe, Middle East and Africa