Transmission

Does anyone know of a hack that would allow me to run two separate versions of Transmission at the same time. I need to download torrents from two specific different ports, so I need two separate instances running at the same time.

If I try to get a torrent with a particular tracker only, it won't download. But all of the torrents from this tracker has like 700 seeders, and no one else complains about it not working. Also, when I use a proxy, which is very slow, it works. So it must have something to do with my router or ...