OK. We are golden with respect to getting the network reactivated on the Windows guest. One down, infinity to go. Thanks for the help.
There was one wrinkle in all this. I had to log on to the guest as a local administrator to configure the nic driver. Windows explorer (not IE) reported a server error when I logged in as the domain admin and tried to open the computer management window.
Explorer.exe server execution failed.
And in consequence I could do absolutely nothing until I logged in with a local user profile.
This is apparently due to the fact that Win7 handles roaming user profiles somewhat differently than WinXp. Evidently, if you do not have a network connection to a remote user profile then the OS chokes. Just a heads up for anyone else in this situation.