Yes, it's the library filter, I have 16 kits which are BFD2 kits, that come up as unknown. All the kits I have edited do come up as unknown as well, so it would be good to tag them as well, though if the only ones in the unknown group are user kits, then that would be OK.
Though, 179 kits to edit is not an encouraging thought.
It would be good if we had a detailed description of what makes up the XML and kit files, there seems inconsistences between files and data such as info_path doesn't seem important (I assume it relates from where the file was created, as the path often doesn't exist - so why is it there?) . I also assume the order of data is not important either.
I have compared two kit files with one that is tagged right and that isn't, and I cannot see any difference in the files.
One thing is for sure, if you edit an XML file, your need to rescan the content locations.
I have edited successfully kits and grooves, etc that did not show not in the appropriate location in BFD3. The kit file has data such as info_name="X Drums Kit 4A" info_librarylong="JEX" with some of the kits the info_librarylong="JEX" is missing or simply does not exist. That's the key string. So to edit a number of files quickly, I used textcrawler. With text crawler I would search for a string and replace it with another, pending if the librarylong was missing or to change it. Such as, search for info_name="X Drums Kit 4A" and replace with info_name="X Drums Kit 4A" info_librarylong="JEX" this way you are creating the info name and just add the librarylong data. Some files I had to just have to edit the librarylong string, others had to create the librarylong string. With textcrawler (freeware) I could do a number of files at the same time, because you select the files to search then edit only those automatically. Do make a backup first before doing this, so you have something to back to! You must rescan all data paths then afterwards.