So, I managed to fix my issue described above regarding connecting to my network.
This is how I did it in the end:
1) Look through the top of your receiver and you see should the mac address - note this down
2) In your router settings force it to reserved an IP address for this mac address
3) Turn the receiver off for a good period of time. I left mine off over night and in the morning it was able to connect to the network.
I hope this helps people who were having problems with it hanging on "applying settings" in the Network settings menu.
Good catch. For the steps above, you can just add the router's MAC address to the DHCP assignment table (which you did) and then just reboot the router, which will force the 1122-K to obtain a new IP address, along with everythings else on your network.