FWIW - I’m running the Core on a Synology NAS 916+ which was on DSM 7.1.x. On another thread around here Roon server dont' start after after today’s Roon upgrade - #6 by Moonshiner there was a suggestion to do a manual update of the DSM to a 7.3.x version. After hesitating for a bit…I took the plunge and followed the Synology instructions exactly (step-by-step updating) and it all just instantly worked with Roon Core and Database suddenly all accessible again. Magic!
Only thing is I had recently done a complete back-up of the NAS, so had a level of comfort I wasn’t going to lose anything on the NAS if it all failed miserably. But in my case, all worked out fine. Big relief and I can get back normal life 