From what ive heard and noticed a lot of people have problems and issues with the software and functionality. I got it to work but not to my liking.
So instead, I got an older computer from my house and parts I had lying around...
120 gig HD, 1.6 ghz single core processor with 512 megs of ram. I installed windows 7 on it (I get it for free from my college
and stripped it down to the essentials, only uses like 300 megs of memory from bootup) but linux, or ubunto (free) would work great.
I got remote desktop working, set up the dynamic DNS, and a free VPN software that takes minutes to set up (Called hamachi). Now, this computer is connected to this file server I created (for a total of 0 dollars mind you), and I have the network drives mapped through my network, and the same drive mapped again through the vpn software. So if I ever need anything, all I need is an internet connection and I can access this desktop from anywhere. Where as the USB connected to the router can only be accessed if you are on the network. (although you might be able to figure something out with some vpn software)
It seems to access and copy files almost twice as fast, and for me it is much much more reliable. Personally this is my suggestion. Requires a but more effort setting it up, but its much more versatile. Hell if you had a 3g phone, you could be across the country on the go and still access your file server from home