Apparently tech support does not know how to make this work, so is there anyone out there who has this setup and has made it work? I get as far as specifying Cable Modem, and then it times out trying to find the Internet, and I plug in my trusty old Linksys, and I'm fine again...

Uhm.. have you tried cloning the MAC address of your Linksys to the ZA100? Many Cable services are locked to the MAC address of the router/modem... Also is the only thing plugged into your cable modem the Za100 (no voice over IP devices, wireless devices).. The Za100 should be the only thing grabbing an address from the modem.. also does your cable modem require PPPoE with a login and password?

Some things to try ;)
Network > Internet > Internet Setup
That Mac Cloning checkbox ;)
If this is not right and your ISP requires it (many will NOT tell you this).. youll never connect cuz the Za100 will fail their authentication.

TKS No does not require PPPoE, I can play both to the PC direct with "obtain IP Automatically" as well as through the Linksys, with "obtain IP Automatically." Therefore the point of cloning the Mac address seems unlikely to me, but I'll try it.

On the Z100G "Cable Modem" would appear to be the right setting.

No other devices competing. Will try your other suggestions as well.

The other possibility is that the cable modem needs to be reset to forget the current MAC address. If both the PC and the Linksys connect it is possible that you cloned the PC's MAC address to the linksys at one time. To reset the modem unplug it for a couple of minutes then plug it back in and connect the Z100G.

And that was the answer - I needed to select "Cable Modem" and let the modem reset itself - problem solved! Thanks for the help.