That is fine Rich, you are a programmer and know what to do us other poor slobs don't have that knowledge so use what we were told when UEFI came on the scene.
No, it's not that I'm a programmer, it's that I make a good-faith effort to know what I'm talking about before posting. And, if I'm not 100% sure of my answer I test it first. Far too many people seem to think this forum is some sort of game show: "Be the first to post an answer and you can win a matching set of luggage - No knowledge required". How does that help anyone?
In this case, you say you were told disabling Secure Boot was a requirement even in CSM/BIOS mode, and so you disabled it, relying on something you read. If you saw that in this forum, were you truly well-served by having someone who didn't know and certainly didn't test, posting misinformation that you then repeated? Wouldn't we all be better off if people like that kept their hands off the keyboard rather than leading others astray?