Let’s say that I have a “main” folder from which I have COPIED files to subfolder to subfolder (or even to subsubfolder).  That is, the same filename appears more than once (consecutively) in BRU's old Name column.  I want to rename (actually, autonumber) all the files such that the matching filenames are still matching after renaming.  Folder1/FileA= File001, Folder2/FileA = File001, Folder1/FileB= File002, Folder2/FileB = File002, etc in all (selected) folders/subfolders.  I'm assuming (but what do I know?) that the order shown is the order of the renaming, in which case it seems that comparing "last-old-filename vs this-old-filename" would work.
I don’t think this is possible . . . but, again, what do I know?  This does not happen when Folders, Files and Subfolders are all checked in Selection(12).
This would be useful to me because, after my long tedious initial editing sessions, I re-sequenced the remaining of the 5000+ digital images from a recent photo trip.  Then as I selected out (copied) the “top quality” images to other folders/subfolders, I discovered that I had not been severe enough with my initial editing.  This renaming option would surely save me a lot of work.