Thanks for building this!
I was in a band active in the mid 2000s (think myspace era) and we never signed up for, or collected any of our publishing. Somehow, we still stream quite well so have been actively trying to connect the dots on this stuff over the past few months.
They do NOT make it easy, and if you want to collect internationally as a DIY artist, its basically impossible. Trying to navigate this is almost a full time job.