Unless you set your user profile options to browse boards with cookies and remember your username & password - there is an issue with gaining permission to various areas of the website. Will try to fix this, this week or simply make these two things a requirement. I've updated your profile for you, so if you try it now it should work. Sorry about that.
I've come across this before. Some members change the deafult option (quite legitamitely) in their profile, but it causes problems with permissions across the site. Unfortunately I haven't had a chance to fix this yet - but I'll make it a high priority.