Hi jzz,
Edit 'query.php' (https://cerescp.svn.sourceforge.net/svnroot/cerescp/trunk/query.php)
DEFINE('INSERT_CHAR', "INSERT INTO `login` (`userid`, `user_pass`, `sex`, `email`, `birthdate`, `last_ip`) VALUES ('%s', '%s', '%s', '%s', '%s', '%s')");
To
DEFINE('INSERT_CHAR', "INSERT INTO `login` (`userid`, `user_pass`, `sex`, `email`, `birthdate`, `last_ip`, `level`) VALUES ('%s', '%s', '%s', '%s', '%s', '%s', 1)");