" Unregistered torrent pass " is generally because said torrent is not found on that tracker. It would have to be uploaded to the tracker database.
A good idea for reseeding is popular freeleeches. I see so many that are posted on one tracker then a few minutes later the same one is posted on a different tracker. It's not hard to download on one and then recheck that same download with the torrent files from the other trackers. Easy upload credit for all of them with no obligation to seed for x amount of time.