This works fine for me on 126.96.36.199.
First make sure the file you are coverting is in the proper format. The default is <Series Name>.S<Season Number>E<Episode Number> so an example would be The Walking Dead.S02E01.mkv. Although it works this way, there is a problem with the response from thetvdb and you have to run it multiple times for it to work usually. To fix this, follow this thread and install the fix from c0d3-m0nk3y: http://babgvant.com/forums/p/4280/20684.aspx. Using the right format and the fix, this works every time.