here is the debug:

1064: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') GROUP BY members.name' at line 1
SQL:
SELECT members.name FROM `roster_items` items LEFT JOIN `roster_members` members ON members.member_id = items.member_id WHERE items.member_id = '19' AND () GROUP BY members.name
File: membersinst.php
Line: 194

The Problem is in memberinst.php, line 168:
$items = $inst_keys[$row['clientLocale']]['Alliance'];

German localization needs Alliance to be replaced with Allianz