Ah, working with computers is such a never ending joy!
After I posted I shut everything down and went outside to do some yard work. Couple hours later I fired everything up and tried again. VOILA! Everything works.
FLMsg mode follows FLDigi.
Message reception works.
My guess - and it's a stretch - is that after installation a reboot was required to get the xmlrpc address and port to work.
A word about "Transfer direct to executing flmsg".
I've been using it that way with the windows versions for years and have never once had a problem. And it's working now on Ubuntu.
Thanks for the prompt replies everyone.