I have similar problems. it seems after upgrading to Domoticz 2020.2 that randomly z-wave devices report wrong values or no values at all or even get “disconnected”. I struggle already for several weeks with this problem. Also the blocky-scripts behave strange sometimes as a result of those wrong or ...

hallo, I have the same problem.
i used a blocky with a dimmer:
"if dimmer in room > 10% then switch lamp outside = on" It does not work.
If I uses a regular switch:
"if switch in room2 = on then switch lamp outside = on" works

Decided not to switch to the NAS because DSM7 will not be supported (yet). Instead I upgraded the system to a Raspberry pi4 with a SSD drive (to get rid of the SD-card). The systems runs now completely via the SSD-drive (boot and operational).

Are the nod-id's and names than also updated. Is this also stored in the database?

I run Domoctiz for several years on a Raspberry. Now I have a new Synology NAS and want to move the whole Domoticz system to the NAS. Installation of Domoctiz was easy and without a problem. 8-) For the Z-wave network, I use a Aeotec Z-wave stick Gen5. As I already built the system for several years ...