Got it Monday. After much gnashing of teeth and time on the phone with Apple Tech Support, I finally got all 5 Macs on our home/office network backed up, it works perfectly. All these issues related to Apple's light documentation (which omits several key points).
• Be CERTAIN every computer has a name in the Sharing preferences folder. No name, no dice.
• Only back up ONE COMPUTER AT A TIME (they don't mention this). Multi backups (initial backup) causes data transmission to slow to a crawl and leads to more failures.
Networking is inherently complex, break one rule, nothing works, same for Macs as for PC's hence the potential snags. But now that it's up and running, the thing is extremely slick at it WORKS very nicely indeed. After backing up five computers (some with a ton of data) the 1 TB drive has 600GB of empty space left. That doesn't suck.