SOLVED my issue of not connecting to Media Manager (Norton 360 Firewall Problem)
The Firewall settings on Norton 360 was the problem, but NOT the Media Manager program permissions. - The problem was in the Norton 360 Network trust settings for each DEVICE.
I had to go into Norton 360's control panel, click SETTINGS at the top, then click MY NETWORK in the list of tasks.
Click CONFIGURE accross from Network Security.
Now open up the Verizon router web site at http://192.168.1.1/, and click "My Network" that lists all the active Device Names, IP numbers, and MAC addresses.
In the Norton 360 Network trust listings, You must set the Set-Top Boxes (IP-STBxx) to Full Trust. Also set the computer running the Media Manager to Full Trust. Find the devices by their MAC address, since the IP numbers may change unless they're static.
If all the deviced are not shown, create the device reference with the name and MAC address from the Verizon router's Network web page. Again, use MAC address because the IP address may change unless they're static (as opposed to DHCP). Note that you'll need to add any divices that weren't already added. The Norton 360 Network trust settings are actually two lists, and rather confusing.
Added devices go in the Trust Control list, but automatically-detected devices go into the Local Network list, but they seem to have to be created in the Trust List manually mu name and MAC address in otder to assign them as Full Trust - WHEW!!! - There oughta be an easier way, and maybe there is, who knows!
Now the YouTube Widget should be able to connect so you can play videos and do searches!