To make a post you have to register with your real e-mail address.
After that you'll recive a mail in a minute or two, in it you'll find a link that you have to click to activate your user.
For people in the guild:
After you have done the above you go to the groups in the menu row, there you'll select Guild.
After thats done you'll have to press the button "Mer information", then you get to the next page where you have a new button to click.
when thats done i'll upgrade your account so you'll get full access.