Re: Import selfmade music into Soundtrack Pro (interpreted)

Yes - use the Soundtrack Loop Utility. You can set BPM, key, genre/style/instrument/etc, and more, just like Apple's loops.

However, if all your doing is mixing the final tracks, it doesn't matter if STP recognizes the key/bpm of your audio, really, unless you're mixing loops or tracks with different speeds and keys. It's useful if you want to use a filter that uses BPM information (like reverb, delay, auto filters, etc), but you can set the project's BPM and key manually in the project settings.