Well, I had 191 GB of MP4 files that I could not use MediaMonkey to get the track numbers from. All the filenames were messed up because MM put 00 for the track numbers because it didn't read the track # (#) field from the MP4 files. I was able to use a different program TAG & RENAME (http://www.softpointer.com/tr.htm
) to rename the tracks based on the track # field. (Mine are set up <track#:2> - <artist> - <title>). I'm not sure why MM would only show blanks when I opened these MP4 files, but it will not. I tried different ways, but no luck. Tag and rename immediately recognized the track # tags in the MP4's, so I would have to say there is definitely a bug in MM. Honestly this is one of the very few problems I've had with MM. Just thought I'd report this.
What I did after the files were renamed with Tag & Rename was to then import the folders with the MP4's into MM and then Auto-Tag based on Filename, then MM put the track #'s into it's own place for track #'s, which must be different than the files I am working with.