In response to my own post I have found a way around the interface being incredibily in-accessible and non standards compliant.
Logging a web browser (PPC 2003SE IE) to 192.168.2.100/iframe_login.htm (where 192.168.2.100 is the local IP address of the n2100) allows the user to login and then can access any page on the interface. However it is necessary to know the exact URL as the menu system does not appear. However using Opera 8.6 for PPC it is possible to use the menu system but it is still necessary to start access through the page above. It would be very useful for the entire menu system to comply with with w3c rules and therefore be more accessible and standards compliant.
Also, the initial page uses what web usability expert Vincent Flanders refers to as "Mystery Meat Navigation". There is no clue as to what the meaning of the buttons are until you mouse over them. This is poor design.
The front page of the web interface is flash driven - which is big problem, if your not running flash or if you've blocked it (I block flash). Its really simple to just use good old HTML to do the same thing and be compatible with all the browsers - and a better user experience....
Flash serving and flash on the local machine takes up a lot of CPU. There was an article on flash in PCW or PCPLUS, it takes 16% CPu usage even when idle on the client. Not sure about on the server.