Yea, initially when Twitter didn't work, I tried that a few times. I never got any confirmation, but I tried logging in with the credentials I used anyway, but "No user found".
Hmm, the site has had a few new sign-ups in the last couple of minutes so I don't know what the issue is. Try registering with a new username and after clicking sign-up, wait a few seconds and click on the logo at the top of the page. That should do the trick.
Not sure. Tried it in different browsers with different usernames, different passwords and different emails. Nothing happens when I click register. When I go to the homepage, there is no indication I'm signed in. When I try to login with any of the accounts created, it says "User not found".