That link made all the difference, vagskal. I had gotten a Whitebear from somewhere else, and it didn't do a proper install.
So, now I see LMS (by Whitebear), but I think the bear is confused because I still see all the other things I listed last night—Main Library, Jaguar:Rick, and Logitech Media Server [Jaguar].
Further, I no longer have control of Transporter, although now, for the first time "Transporter (by Whitebear)" appears in the Playing Now stack.
Regarding the Transporter, the first item in the Whitebear stack of available songs is what now shows on Transporter's display. Also, when I try to take control and send Transporter a different file, the message I get is this: "There was a problem controlling the selected DLNA device. Double-check your devide, server and network settings."
I suspect that I'm now encountering the DNLS conflict you suspected last night, but there may be other issues as well. For example, the DNLA library in Whitebear shows that nothing is loaded.
Anyway, I feel we're almost there.