Registration is done on the main page, or you can click the link in this post. This function has just recently been added, which is why you couldn't find it until now.
I'm not sure if I was having a problem with registering because of the server error. I cleared my cache out...tried it again...with the same results. After two more attempts (yes, I'm stubborn), I decided to try a 8 letter password instead of a 4 letter. It went thru. Is the password error linked somehow to an error you would receive if you didn't use a password of the correct minimum length?