How to Filter Rigs marked as a Favorit?

Here is a way to do something very similar:

Right Click on the Column headers - add a checkmark next to "Favorite" (or "Show All Tags")

Move the slider at the bottom to the right, until you can see the "Favorite" header.

Click once to put the Favorites at the end of the list. Click it again to put them at the top of the list.

Allow me to share with you my super, secret method for doing what you ask (if I'm understanding it correctly).

Think of a magic word that has nothing to do with Kemper, Amps, or even music (in my case, its my daughters name).
Enter your magic word in one of the available comment fields.
Display 'all rigs' and enter your magic word in the search box.
All rigs with that word in the comments will now appear regardless of what folder its in.

You can also use several magic words for several different search criteria...

Hope this helps...