Any idea's on how I can progress?
find a manual for the router. As it's not a common item some screenshots posted somewhere might help.
Note that the WAN side of a BT ADSL connection does not use DHCP (referring to it as such is confusing)
Also you didn't address my point of setting the external IPs on the client devices.
Phil
MaxDSL - goes as fast as it can and doesn't read the line checker first.
MaxDSL diagnostics
Are your kids pirates ? Limewire, Bearshare, Kazaa, BitTorrent, eMule are all tools of the trade.