Well, try ipv6.google.com to verify you're running IPv6. You can also try http://test-ipv6.com/
to see what your address is. Since you're logging with with your own ID, that address should be static. One thing about Windows 7. Most operating systems these days provide a MAC based address and a random number address. The random number address is the one that's used when you access the Internet, but you need the MAC based, if you want to reliably reach your network, as the random number address will change periodically. Windows 7, by default, uses only the random number address. To enable the MAC based address, you have to do the following:
1) Run Command prompt as Administrator (right click on icon to select)
2) Enter: netsh interface ipv6 set global randomize*identifiers=disabled
In the gogoClient Utility, you should also enable routing advertisements.
After doing that, when you run ipconfig, you should see at least 3 IPv6 addresses assigned to your computer:
1) a link-local address that starts with FE80 and contains your MAC address
2) a MAC based address containing your MAC address
3) at least one random number address. These may accumulate over time, but only one is current. The rest are deprecated, but still functional, for connections that started before the random address changed.
Also, the MAC based addresses will have FF:FE inserted in the middle of the MAC.
You should also see your tunnel addresses on the status tab of the utility.
My subnet experience is only on the Linux version and not Windows, so I'm not sure of all the details on Windows. Also, one thing I forgot to mention earlier is the Windows version has the "HomeAccess" feature, which gives you access to IPv4 devices over the tunnel. Again, I have no experience with this.
So, at this point, make sure you can see all your IPv6 addresses and can connect to IPv6 only sites, such as the ones I mentioned. Once you've done that, see if IPv6 addresses, other than the link-local, appear on other computers on your network. I assume the raspberry pi should do this, as Linux has supported IPv6 for many years. I also get IPv6 addresses on my tablet and smart phone. This will verify that IPv6 routing is working. Also, you may have noticed that gogoNET site has a forum available, where you can ask questions about the client, the service and IPv6 in general.
BTW, you can install an add-in called "showip" in Firefox, which will display the address, IPv6 or IPv4 of the web sites you connect to.
As for the raspberry pi, you may have to ask someone else, about that, as I have no experience with them. Again, you can post your questions in that forum. However, if you're content to leave the Windows computer as your IPv6 router, then you don't have to install the client on the raspberry pi. It should obtain an IPv6 address on the subnet as soon as the tunnel & subnet on the Windows box starts up.