ar_ni - Cheers.
Emilie - I don't know about the new process, but I sat stage 2 quite recently. All the advice I can give is to learn the motivational booklet word for word as you'll get questions from every single section of it.
As for the computer tests... Well they've probably changed, but as they were you used to get a break between each batch of tests so just take your time. You're not timed overall, but once a test starts then there's no pausing or stopping until it's done. You get practice questions, so make sure you understand what you're doing as you get a chance to do these at your own pace and as often as you want.