I accepted my alpha invitation and was asked to choose a username. I entered a username (my firstname and second name without any spaces) and got a message saying Username Claimed with a picture of a party hat. But I wasn't redirected anywhere. I just had to keep entering a username. I tried again multiple times with the same username and the same thing kept happening. I tried again with an underscore separating my first name from the my second name and that seemed to be accepted and I was redirected.
