Another update.
I did use the same IP address in both places. Seemed to work (see below).
I found some threads where people said to try the 5500 Intellisync from the Sharp USA site. I did that and have gotten further! I now get some communication between the Z and the PC, and the sync starts. But then it gets that message about not finding the Palm desktop software. I found
a thread saying the older Palm desktop software was installed under C:, the newer under C:Program Files, and the guy with that problem found some older Palm Desktop software that went under C: and got it to work that way. I'm not crazy about that even if I could find the old stuff. I wonder if the new stuff gives an option where it installs? But even if it does, what happens to all my contact files, etc.?
Oh, also on the sync setup, the Intellisync does not seem aware of several fields in the contacts of the new Palm Desktop.
BTW the Trisoft procedure at one point suggested trying to telnet to the Z to check the communication, but I have yet to get that to work. But the connection seems to be there anyway. Ping works from the Z too. I now have to deal with this other problem.
Geez, this is like pulling teeth.