> If I don't know what I'm doing wrong, I can't fix it

Most of programming btw is like that. Google throw an exception with a better error than "undefined is not an object". Maybe it's easy for me from the outside to pinpoint the problem, but it's usually about reading between the lines.

Their support is indeed poor, but you are not entitled anything and probably the lesson here is not to build anything serious on 3rd party platforms where you are unsure about licensing, legal questions. I've been burned once by SoundCloud legal team for using their public API.