I tried creating new CA database containing some games copied from PGN file (two methods - opening PGN and copying, and separately batch database convertion). For some reason those games fail to open (the board window flashes for a short moment and disappears).
Note: I happened to survive similar problems with CA 8.1 on Windows (reinstallation being a remedy) - looks like in some cases CA corrupts some of its internal data (I haven't diagnosed it truly, but likely reason is that it fails to open direct tree, or maybe engine evaluations).
I am yet to try some workarounds.