I was really confused about the "fill in all of the required registration fields" as well because when I clicked on the button that says "submit your design", all I got was the e-mail I am supposed to send it to. No registration fields. I read the guidelines at least a dozen times to make sure I did not overlook anything, that there was a separate link or anything where I have to fill in those registration fields but nope, couldn't find anything.
So I just submitted my poster to the e-mail-address but I'm really uneasy if it really worked. Shouldn't there supposed to be at least an automatic response that your e-mail was received? How do I know that my poster got where it was supposed to be going?
I guess I just have to keep my fingers crossed and hope that Bioware won't add any of those registration fields now and all the other entries that reached them before that become null and void.