What version of Replay Music do you use?

Can you upload your recording somewhere so that we can try to play it?

Like any other individual song tagging program, it can't only recognize can't tag all the songs. The tagging doesn't work for you at all?

I suggest you to visit Applian Users Forum as well
http://forum.applian.com/forumdisplay.php?f=5
It might have the answer to your problem already. Plus Applian support is usually very fast at answering questions.