I couldn't pull up your link..
At any rate, you need to have the Bittorrent module installed on the DNS. This is done through the DNS configuation web page. You can find the Bittorrent module on dlink's product support site for it. Download that zip file, extract it, and then install the extracted file on the configuration web page. I believe it is under the tools option.
Once it is installed, you pull up the web interface and log in. This time you log in under "applications" and not the configuration.