line 193:

$query = 'DELETE FROM '.AVAILABILITY_TABLE_RSRC_EVENTS.'
                       WHERE event_id = ?';
	    $db->Execute($query,(int)$params['eventid']);

debug:
(mysql): DELETE FROM cms_module_availability_rsrc_events
                       WHERE event_id = ?<br>
Error (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 '?' at
line 2

solution:
$query = 'DELETE FROM '.AVAILABILITY_TABLE_RSRC_EVENTS.'
                       WHERE event_id = '.(int)$params['eventid'];
	    $db->Execute($query);