Actually got this working last week, was just about to post when I had to go away quickly. Anyway, got it working, here's how:

1. Ran 'Network Card Config' or whatever it's called - from Knoppix menu - cannot remember exact name, currently under Windows :( Pretty obvious really - as well as configuring the wireless side of the card, you have to configure the standard IP parameters. Bit embarassed about forgetting that ;)

2. At the end of the 'Network Card Config' wizard/dialog sequence, the 'Wavelan Config' thingie automatically starts (although you can also access it from the KDE/Knoppix menu). Only one minor problem though - for some reason the (WEP) encryption key is not taken. In fact the only way to input it is as root - so I simply opened a root console and typed
Code:
iwconfig eth0 essid "my setup" enc "s:xxxxx"
Thanks garyng for the encouragement, and sorry for not posting earlier (been a manic week). Anyway, besides the root issue for the WEP key, I'm impressed with the networking and wireless config tools - far superior to what I encountered a few months ago with Mandrake 9.0.

Cheers

Chris