I had the same problem with Bittornado until I upgraded to version 3.18, which unlike previous versions, has encryption. I have read that Comcast uses bit-shaping? to limit bittorrent activity. The encryption fights Comcast's attempts to limit BT activity. Just like you I wasn't able to upload after completing a torrent, but now with 3.18 I can upload after completing just fine. uTorrent is terrible for initially seeding a show because there is no super seeder mode, so sometimes you wind up uploading 1.75 copies of the show just to get it initially seeded. With super seeder mode, it is guaranteed that you will only have to upload 1.00 copies of the show to get it initally seeded. I've had some issues with Azureus, like my connection dropping, and it is a resource hog.