@Roger-Explosion I had to change the
SMBIOS to
iMac16,2 to avoid the Firmware Update Issue. I changed it back to
iMac19,1.
Having some
Bluetooth/WIFI issues: BRCM4352. But everything else worked just perfectly.
Thanks heaps that's a good one - the issue I'm having at the moment with the included EFI folder (with the 19,1 Vega Config.plist) it's doing the black screen thing when booting from the installer USB. (The screen is on but displaying black, not flickering on/off).
I remember I had this issue with my previous build on this machine too - which was I think Catalina.
EDIT: wow ok so the monitor that you use for the install matters.
On an old 1080p LG monitor - it shows the boot screen and begins startup.
On a new 4k Samsung monitor - it's black!
EDIT 2: I also had to disable SecureBootModel from Misc -> Security -> SecureBootModel to prevent the computer from constantly restarting during the part of the install where it tries to continue the installation after a reboot.
EDIT 3: I had to re-enable SecureBootModel after it finished that part of the install otherwise it kept hanging right at the end of the progress bar. This is wild.
EDIT 4: Up and running.
Used Hackintool to map my USB drives (much easier than Opencore's probing thing) to create a personal Kext for the ones that I want to use.
Thunderbolt 3 working great with Titan Ridge card installed (same config that worked under Mojave). Must turn on TB3 devices before boot though (again same as Mojave).