I just completed the registration process which was fairly easy.
I had some irritations with PayPal. It seems that PayPal detects that I'm living in Holland and presents me with the Dutch language PayPal site and Dutch payment options which differ from the UK. I figured out how to get the PayPal site into English and then was able to register a credit card. This registration process took a week to complete because in order to register a cred card with paypal you need to make a £1 payment and wait for the transaction to appear on your credit card statement. You then need to enter a code which appears next to the transaction description to complete registration of the credit card.
I really happy with the online study notes and the website.