I set up a bunch of schemes that I use in my audio files, and the guessing is always correct when I use "Guess tags from filename" in "Edit track information" - however, the collection builder doesn't seem to use my settings, and it always guesses incorrectly, it found the artist names, but not the albums, and every file is in an "unknown" album.
"Guess tags from filename" does guess the album correctly. It would improve usability greatly if the collection database would be built just like that.