Well, I'm not completly sure because I don't use Azureus, but it should say something like "Download Completed" or "Download Done." I have heard that the download is still not done if its says 100%, you have to wait fot that message. Hope I could help.

EDIT: After looking into it more, yeah when it's done, it should be in the "bottom part" (Completed/Seeding Torrents area). Hope that cleared it up.