After a prolonged absence from my system I'm now back at the keyboard. I'm sticking with the Dianemo S system for now but have some new issues 
I noticed that previously when any machine on my network was using a lot of bandwidth, i.e. downloading movies etc. then the core/nerve centre would crash. I've tracked this down to the onboard NIC I believe, so I disabled it and fitted a USB NIC. I did a clean install of 12.04 today and then installed Dianemo from the 1.17 deb. Internet connection worked fine with Ubuntu through the USB NIC, obviously or Dianemo wouldn't have installed. As soon as I rebooted the machine after the installation there was no network connection to the internet from the core; the network settings show no external Mac address, or IP address. If I go to the desktop and try firefox, or any command line command, such as apt-get.....etc there is no network connection.
So how do I tell the system that it should use the USB NIC for the external connection?
Cheers
Matt

I noticed that previously when any machine on my network was using a lot of bandwidth, i.e. downloading movies etc. then the core/nerve centre would crash. I've tracked this down to the onboard NIC I believe, so I disabled it and fitted a USB NIC. I did a clean install of 12.04 today and then installed Dianemo from the 1.17 deb. Internet connection worked fine with Ubuntu through the USB NIC, obviously or Dianemo wouldn't have installed. As soon as I rebooted the machine after the installation there was no network connection to the internet from the core; the network settings show no external Mac address, or IP address. If I go to the desktop and try firefox, or any command line command, such as apt-get.....etc there is no network connection.
So how do I tell the system that it should use the USB NIC for the external connection?
Cheers
Matt