I wouldn't recommend this piece of software. I've used it extensively in the past, although more as a tagger than a cataloger, and my problems with it made me go the foobar2000 + Mp3tag route. The renaming function is essentially broken, and it doesn't recognize the whole gamut of tag types nowadays. Also, it was a pain to re-tag files, and I think that you couldn't add custom tags. Seriously, if you want a cataloguer, there is a good range of them compiled by tomos
here and for a tagger there are really good options, like the freeware Mp3tag or almost any audio player nowadays. Add to this that the project has been abandoned by everyone.
In fact, Mp3tag is the only tagger I would recommend. I tried one of two commercial offerings (Abander Tag Control and Tag Clinic) and I went quite disappointed. The first one is a terrible work of GUI design, although it seemed quite powerful, and Tag Clinic is overhyped by some people, since it's a really dull program.