actually, on a PC, i used Internet Explorer, and Chrome, after a bunch of CTRL + F5ing and closing out and retrying in both browsers, i was able to get into the birthday fields by clicking into the next field, and doing SHIFT + TAB to go back a field, and fill them in. I even tried compatibility mode in Internet Explorer.
It looks CSS related if i had to guess, stuff is all overlapping and conflicting or something.
I do apologize for the issues people have been having with registration. The date problem has now been fixed to my knowledge. It was a dumb mistake on my part. Thank you so much for reporting this, it fixed some other problems I have been having.
I have not abandoned the site, just a bit back logged with the holidays and the work that pays me. I have marked all the things that are done and stamped the status on the ones that I will be starting tomorrow. :3