Going to try to be as specific as possible as I am not allowed to share my source file (client confidentiality does not allow it):
- I created a set of icons to be used in a toolbar
- Then converted these into symbols
- Next I used these icons in a toolbar
- And further converted this toolbar into a symbol (to be used as a UI kit)
the result is, that all the symbols I reused in the toolbar have disappeared from both the symbols overview (Alt+2) as well as from my UI-kit.
Edit: I did some more digging, this happens when you insert something from within the UI-Kit (Alt-7) into the master symbol. When inserting from the symbols overview (Alt+2) everything is fine.
Best regards, DJ