I've had this issue for several of the last versions.
I import a NZB into Alt.Binz and the download starts. I am limited to 20megabit down so it records 2000 on the graph at the bottom. After awhile, I don't usually watch the downloads for longer than a few minutes, but eventually the download slows down to just several hundred kilobits. I then switch from the US to the EU server my provider allows, start and stop Alt.binz and I'm back up to full speed. Soonafter it is slow again.
I installed grabit and get full speed the entire length of the downloads, several hours.
Unless I can find a resolution I'm going to have to give up alt.binz and I hate that because I hate grabit compared to this.
Any option to go back to something like version .036 or so of alt.binz?