Tonto doesn't use a gallery.ccf file in the same manner PE does. Tonto builds it's own "Icon Library" from all the icons that are present in an open ccf. So, there are no unused icons in this library. In fact, the library (unlike a gallery) will contain different icons depending on the ccf that is open. Although Tonto will open a gallery file, it's not intended to be the source for button graphics (like PE). There is also no way to delete an icon from the library, if an icon is present in the ccf, it's in the library. The ONLY way to delete an icon from the library is to change the icon on every button on which it's loaded. There is no delete function in the library.
I would think that the best thing to do if you have say 4 instances of an icon with small differences, is to use Tonto to globally replace 3 of these instances with the one you want as described above.
Again, I believe the OP is mistaken when he says there are "unused" icons in the library. What he really has is several itterations of the same grapic, but all of them ARE being used at least once in the ccf.
