Thanks for getting back to me Ian,
It listed them as "C on Silver2; E on Silver2; F on Silver2; G on Silver2; and H on Silver 2".
As you say, that proves that they are connected, although I dont understand why when the search was for a specific drive, it produced the host machine, - but maybe this is how it works.
Also, I've been finding out about mapping a networked drive as you and gah789 suggested.
That seemed easy enough, once I knew what to do. And I disconnected it again too, for practice.
That certainly seems a good workaround for the moment, but I'd like to get the workgroup working if I can, because with several computers and several drives on each, it might be difficult to achieve full two way file moving all through mapping.
At the moment, the XP machines use MSHOME, but I understand that I might need to rename the workgroups to WORKGROUP when I bring the Windows 7 machine that I'm assembling, into use. (I'm confused to see, via Belarc, that the Linux system in the Technicolor router is already in WORKGROUP, - but nothing else is.)
Thanks for helping.