In Azureus, this is what the
health indicators mean:
gray - means that your torrent is stopped,
red - means that you're not connected to any peer,
blue - when seeding, it means that you're not yet connected to any peer,
blue - when downloading, it means that you are connected to some peers but the tracker is down,
yellow - means that the tracker is ok, you're connected to peers, but you don't have any remote connection. You may have a NAT problem if your torrents stay on yellow status all the time,
green - means that everything is going fine.
An inf ratio means you have only uploaded, not downloaded.