Is there a way to move "back" and "forward" through the Library?
For example, I'm editing Symbol_1, then I move to Symbol_22. Now to get back to Symbol_1 I need to find it again in the Library and double-click on it. Is there a shortcut for that?
As far as I know there is no memory function for selecting items in the library.
No, but you can always use the library search option to widdle down the number of items displayed. It'd be a good feature request as I find myself hopping between specific movieclip depths on common clips often. Sort of like a clip/depth bookmark.