Well, it's back up and running. It was a little painful, but not too bad. Thought I'd share about it here in case it helps someone else.
I followed this excellent guide to do an update on my current setup.
The tutorial was excellent. I decided to replace the USB key I was using to a different one, so I burned the boot image onto it, and started things up. Once I got it up and running (after a few hiccups), I found the Synology using the assistant. It said that my configuration files were gone, and I had to reinstall. Using the .pat file I was able to do so and got the Synology back and functional.
While all of my files were still there (big sigh of relief), all the configuration (downloaded packages, settings, etc.) were gone. My guess is they got corrupted, and that's why my Synology died in the first place. So I have to re-download all the packages I had (not a huge deal) and redo some of the settings. So far, the Plex package retained all its settings, which was fantastic Remains to be seen how the others will do. Hopefully it will be fairly painless.
I'm also planning to build a second Xpenology box to act as a backup server, in the event this ever happens again.
Thanks to Polanskiman for the excellent tutorial, and to Jun and the other devs who made this release possible. Very happy to have my server back, and I look forward to trying new features out.