Problems using bittorrent

[shatam bhattacharya]

hello list,
          I am using a DSL-502T (Dlink make) router with a Realtek ethernet card to connect to the net on a sarge system. The settings are working fine. Recently I installed bittorrent by apt
apt-get install bittorrent-gui.
But when ever I try to down load any file, using
btdownloadgui abc.torrent
it starts allright but after 20 or 30 % the download stops. curiously it starts uploading and the process hangs at that stage. Any clues
Shatam bhattacharya