Hi Neil,
I found that I had to restart the router after connecting the B2 to it via an Ethernet cable to make it connect.
For the WiFi issue - have you got the WiFi dongle (marked 802.11n) plugged into the B2 - when you run 'Setup WiFi' (Settings menu) does the B2 display 'Scanning' and then a list of networks it has discovered - are you able to select your network SSID and enter a password - do you press NEXT to connect?
Let us know where in the process the setup fails and we will try to help further.
Paul
Brennan Support.