STUCK on Monterey install at Installer Damaged error

Hello / Help!

Longtime reader and personally not comfortable in this milieu, but here goes:

I've been working through the Dortania guide for two days, and keeping as tidy a config & file structure as possible. Can't figure out why I keep getting an error at the Mac Installation screen (from Recovery) at "about 17mins" loading screen, throwing an "installer damaged, redownload and start again" error.

If anybody could explain where I've got thing crossed. I can't really read the Mac UI installation logs or the OC.txt. Any advice or help on my files is most appreciated. Here's a link to the work so far:

Attempting to make the Monterrey build w USB (non-web) version of on hardware:

CPU: Core i74790 Kaby Lake GPU: Radeon Pro WX 7100 8GB RAM: 64GB 2400MHz DDR4 Motherboard: Gigabyte - GA-Z270-HD3PGA-Z270-HD3P Screen(s) Number: 3 (2 monitors, 1 HDTV) Screen(s) Resolution: 1080p Audio Codec: Apple ALC - Realtek ALC887 Ethernet Card: Wifi/BT Card: Intel® GbE LAN chip 

Thus I figured load as an SMBIOS at iMac18,3 on this OS as is probably the best use of the existing potential for an Editing platform on this hardware. (LMK if you see a better option)

I have been all over the guide for troubleshooting. I've also changed the time in Recovery's Terminal to Sept 2019, Sept 2020, Sept 2022, updated to newest Catalina (current build running) and loaded recommended Kexts, Drivers, SSDTs and ProperTree settings. My experience prior to this has all been with many prev. generations of auto-setups in programs best left unmentioned here, so bear with me please.

Thanks for your time!