not that i would know bout networking, but if you use a live how should the changes you make may be persistent after a reboot?
so:
how did you create the live-debian /where do you got it from?
how did you put it on the stick? unetbootin?
please add the links.
check this:
http://cafelinux.org/OzOs/content/pe...ozos-usb-stick
or similar how-tos.
installing debian on the stick aint an option?
you may also unpack the live-iso and make the changes you want, if thats the way you wanna go:
http://www.debe17.com/web_pages/dean...apr08.php.html
it might look a bit frightening, but should work like a charme as its a step-by-step how-to.
greetings