Happy new year and great to see this thread is still active. My copy of your initial i7 z370 build still works fine and I left it on Catalina (10.15). Unfortunately I now have to upgrade to a newer OS (I don't really mind which one) due to my FinalCutPro libraries not being compatible with my new M1 MacBook.
Should I upgrade straight to Monterey? Or rather Big Sur if that has better compatibility with this machine?
Can I use the apple software update functionality or do I need to update my EFI first / do something hackintosh specific? I have forgotten most things unfortunately, so I am not sure if the Update #50 in Post 1 is for this purpose or not.
The safe mode / BIOS issue was due to an empty battery btw, I switched it and now my mackintosh boots right away every time