Thanks - it would have been great if customer support had done that for me as well. Maybe somebody in Support could update the download link to point to the 64-bit app, now that macOS Catalina will reject the 32-bit app.

I've decided that waiting for a 64-bit update to the OpenDNS Updater app for macOS was not satisfying. It seems that to update the app from 32-bit should not be impossible work, it ought to be rather trivial. I'm not cognizant of the software package...