Looking around the site, I was not able to find clear license terms that related to copyright of the actual music tracks produced. I am not a lawyer, but to me it is critical that copyright (and not royalties) is clearly spelled out. The product lives in an uncanny valley between clear copyright interests in musical compositions and software generated derivative works modified by end user input. The only legal information is a mostly bog standard software terms and conditions on a web page. Such pages often change.

Digging deeper in the site does not reduce the copyright ambiguity to me because the example scenarios like a corporate entity picking up content containing the music are dealt with vaguely rather than by pointing to clear licensing terms around copyright. The example of "tracks for a friend" is met with "we don't care." Right now, maybe not. But copyright interest can be sold to someone who does care...and potentially someone who cares because pursuing copyright interests is their business model.

None of which is to say I don't think the tech and music is cool. It just seems that the messy details that can come back to bite an artist sit on the hard work left to do list.