Adam - I'm confused... why are you using link-local IP addresses on your LAN? This is surely wrong, even if you have managed to make it work.

You talk about issuing private IP addresses on your home LAN - by this do you mean 192.168.x.x or 10.x.x.x type addresses, and do you have a working DHCP server operating within your home LAN?

You actually seem to have assigned a link-local address to your router, which may be fooling your 770 into thinking it's picked up a link-local address!

I would recommend you reconfigure your router/gateway on a 192.168.x.x subnet (eg. 192.168.0.1) and ensure your DHCP server is giving out addresses within the same subnet and see if the situation improves thereafter.