Is that the pay for version or freeware version? If you didn't pay for it, that explains alot...the "default" SSL port for Astraweb is 563, but you can use 443...
Also, take a look at the Astraweb's support page, they had a outage and are doing server upgrades...and your using Comcast, make sure they are not throttling you on that port as well.
I'm not sure if my setting is wrong but I'm only getting about 760KB/s with my 6MB comcast. I read that everyone seems to max their bandwidth so I'm wondering what I'm doing wrong. I using Altbinz 0.28.2 with about 6 connections and SSL port 443. Any ideas?