Hi :)
Im' not sure it's your torrent client.
Try to search in announce.php :
Code:
foreach (array("passkey","info_hash","peer_id","port","downloaded","uploaded","left") as $x)
if (!isset($$x)) // problem here, a $ is on more ...
err("Missing key: $x");
replace by
Code:
foreach (array("passkey","info_hash","peer_id","port","downloaded","uploaded","left") as $x)
if (!isset($x)) // now it's ok
err("Missing key: $x");
Good luck.