No it has nothing to do with post count or anything, he cant even logout.. there isnt a specific post count to be able to logout.. You should simply be able to logout, he can't do anything, not even check the store.. he can't even go to his own profile or settings..
Well, something tells me this is an error in the site because i just tried to create a new account myself aswell, i figured he might have done something wrong while registering.. but i got the exact same errors on that account aswell, i think there's an error in the creating account section of the site