We had missed it was available for use during our QAing (we are a small team with no dedicated QA) and didn't intend for it to be available to the public yet. The course editor is still a WIP with a lot of stubbed in features that aren't implemented yet and it is, from feedback we received, very buggy at the moment. It's not ready for public yet.
We hope to get it to a good enough state for public testing and feedback soon and apologize to anyone who was excited at seeing it being available.