I've been trying to register an account for about a week now, but every time I try to press the register button after filling in my details, nothing happens at all. I've cleared my cookies, my age is above the limit, I see no sign of my ip being banned. I'm not sure what to do besides post here.
If you are certain you meet the age requirements and are not IP banned, then you should contact staff. The only other non-bug reason I can think of is that the name you want to use might be already taken or be too close to a name that is. You can check the exact name but unfortunately there is no way to check for close matches.