Right, so I've done the interview. It went okayish, though it was definitely obvious that I was nervous. I had a couple of pauses where I was formulating the next sentence in my head, as I didn't want to err and um.
There are ten questions, and you have 25 seconds after each question comes up to brainstorm, and then you have three minutes to answer it. You DO have a break after every question. Moreover, you can log out after you have completed a question and carry on from where you left off at a later date.
I'm not going to say what the questions are, but it's a mix of competency and ambitions.