The best solution I found to get these things configured for a DSL connection was to save the config to a text file and modify it and upload it.
I webbed into the Thomson router and tried to add a PPP connection. Nope you don't permission to do that as the admin user. WTF?
So download the config after resetting to factory and and add entries with username and password etc for the ppp connection and upload it and it works. So how come I can't enter the username and password in the web interface? Grrr
Don't forget to add a default route to go out the PPP interface and it's easy...
Just a weird web interface.