I've been having some of the same problems others have had trying to get my BESDF41 router to talk to the Internet through the Westell 6100 DSL modem Verizon provided. I discovered a later version of the router firmware on the Linksys download site, which I downloaded and installed without a problem. Then I discovered an updated version of the BESFX41 Setup Wizard and downloaded that also. However, when I attempted to run it, it halted with an error message stating it could not find the license file, even though there was a copyright.txt file (which isn't a copyright file; it is in fact the license) in the same directory as the wizard executable. I checked the original installation CD and I don't see any license file there either. The old installation program had problems, and would like to use the new one if possible to configure the router.
That is ultimately what I successfully did. I wanted to use the wizard because previous attempts to configure the router manually were unsuccessful, and I thought perhaps I was overlooking something the wizard would contain. I've now concluded the problem all along was the old firmware. Once I reflashed the firmware, I had no problems. Still, the wizard should have worked; someone needs to take a look at that problem for those who feel they need the assistance of a wizard.