Same problem here on my C7 - woke up this morning to a corrupt local database message. Using the Diagnostic tool, I have tried multiple soft resets. They all leave me stuck at 15% and I never get back to the hub UI. I've tried restoring a previous version as well - went back to 2.3.8.139. But same result.
Long time hubitat user, since the C5. Have also been plagued with the zwave dropouts for the past year that still don't seem to be fixed (no, it's not mesh related 
I haven't added a device to my hub in a long time.
Just need to it work - mainly because it controls my thermostats.
@bobbyD - will send you my mac in a DM
