Let me first answer your second set of questions:
Blynk App Questions:
What device type do you choose for the OG? My Blynk app just lists it as Generic Board. Does it even matter? This is what it chose after I scanned the QR code for OG.
===> It doesn’t matter. Generic Board is fine.
My blynk app shows no history values, an incorrect distance value and generally looks useless. Clicking Door Button does nothing. Do you Blynk Apps control the OG and show real useful data?
===> Are you sure the Blynk project is in ‘running’ state? Do you see a green triangle button at the top-right? If so, that means you have not run the project yet. By default, right after scan, the project is in ‘stopped’ state.