Forgot to post system info: this is an upgrade from 15 (free version) to Studio 17. Windows 10.
I uninstalled 17, reinstalled 15, and all the old projects listed. The 3 I am concerned with I tested; they loaded up fine. I then did export of the database again and reinstalled 17 and imported/loaded the db file. R17 reports database imported, then immediately throws this error:
Critical Exception
BtException: Driver not loaded Driver not loaded
The application has recovered from the error. It is advisable to save the project and restart the application. Please mail the details of the error to Blackmagic Design, and contact Blackmagic Design Support if the error persists.
If BtException is bluetooth that might make some sense: although bluetooth is available on this mainboard (Asus P9X79 Pro) this PC cannot see the Speed Editor over BT. (I have not yet tested over USB as I do not have a c -> a cable). Maybe incompatible / old driver. Asus does not provide one directly and this is an older board so last official update from them is from 2016. BlueTooth is whatever Microsoft is installing.