Sorry, just reporting this (I'M busy right now, thus no time to find a valid fix): 
the registration is currently broken on elkarte.net. 
http://www.elkarte.net/index.php?action=register results in "Wrong value type sent to the database. Array of integers expected. (current_filter)"
Edit: quick debuggin: 
private function _loadAntispamQuestions($filter = null)
$filter['type'] is set, but the value is empty
Array ( [type] => id_question [value] => Array ( ) )
Temporary fix (for this site) would be to disable the custom anti spam questions.
			
			
			
				This was fixed the other days.
/me looks at self.
works!
Thank you for reporting!
			
			
			
				Thank you  :)