Is working again. If you are one of the people who couldn't activate please login to your account at www.garritan.biz and download the keycard again. You can drag from the browser to the open ARIA player or save it to the desktop and drag from there.
A short video on how to activate
I've emailed everyone who had an issue with registration but a couple of emails bounced back as undeliverable. If you didn't get an email please login to your account at www.garritan.biz and make sure you have the correct email address in your profile.