I can confirm that installing Transmission is the best thing you can do for your DNS-320.
I was ready to RMA my DNS-320 cause it was a total pain in the *ss to deal with, especially with the built in torrent-client. I have zero knowledge when it comes to Linux and networks so I was afraid to tryout installing transmission... Should have known better... Took me a few hours to install, however it made torrenting a totally new experience, especially with the Transmission Remote GUI . I definitely recommend it !