Just to follow up and "close" this thread, an update:
I looked and saw I had only sfz on my system. So I downloaded and installed sfz+ from the Cakewalk store. It has no trouble loading up Sound Fonts as long as you set the mode to PR32 (the default mode gives you a "not enough memory to load Sound Font" message).
(What are these modes in sfz and sfz+, anyway? I found this information in a preview chapter of a book,
Cakewalk Synthesizers: From Presets to Power User by Simon Cann, which I found on the Delmar Cengage Learning website. I can't post links until I've posted two more times so I'll come back and add it later. If you google "sfz modes" it comes up at the top of the list. Looks like it might be a good book to have; it's available on Amazon.)
In my googling about the sfz format, I found an free editor that can be used to convert Sound Fonts into sfz files called sfZed. Again, can't post a URL but if you google for "sfz editor" it'll come up.
So I'm a happy camper -- if I want to use any of my old Sound Fonts, now I can again.