I don't know if others have had this problem or not but I spent the better part of a day trying to get subsonic 4.4 to work on my system. I used the windows installer version and it worked fine within my home network but I could not connect to it externally. All the posts in here only ever pointed to a router issue. I knew it wasn't but I followed all the posts I could find about resolving the problem None of them worked.
I decided to uninstall Subsonic and downloaded the standalone version. As soon as I fired that version up, it immediately started working internally and externally. After uninstalling the windows installer version I did not change my router settings either. The standalone version just works.
Save yourself the hassle if you are trying to get this to work on Windows and use the standalone version, you'll be much happier.
Great product, btw when it works.