Actually, on second thought, although the idea I had for a different approach to that problem would work logically and be easy enough to program, the workaround for the pitfall would require making AKC! less automatic. So, what I can do is specify a user-defined collection type (preceded by ~ or something) and leave those collections intact when running AKC! They would be completely user-managed, the program would ignore those collections entirely and you could, if you deleted the books in such a collection, end up with an empty collection. You could delete it by hand, of course, using either the Kindle or another collection management program, but that's what user-managed means.