Unable to modify AVR's EDID (I could previously)

[ashlar]

Hi! I am trying to understand what happened to my configuration...

I have an LG 77C1 and a Denon X3800H. The LG used to connect to the AVR and the AVR connected to the LG.

After a small amount of time, the display got oversaturated colors. So I reset everything and reinstalled the backup I had done when everything was set up as I wanted it. Using restart-64 froze the machine. I went to safe mode, deleted all modifications and tried doing everything from scratch.

Alas, any modification to the AVR EDID, followed by a restart-64, brought the machine to a freeze.
I can't add anything, I can't delete anything. But I did that previously and it worked.

I tried completely uninstalling the video drivers (Nvidia RTX 3070 here) and reinstalling them from scratch. Nothing.

I attach the original EDIDs for both the AVR and the TV and the modified EDID for the AVR that used to work perfectly.

I need to slightly alter refresh rates for both 23.976 and 24.000 in order to have smooth playback with no dropped or repeated frames and... well, basically it's proven impossible now (I resorted to connecting the PC directly to the TV, using a DP-HDMI cable to get audio to the AVR but that's less than ideal).