Right. I was just saying it is working for me. Let's just wait for a more stable fix which works for all and then this issue would be gone and post #1 rewritten to contain all the info needed on fixing this issue properly.
Glad the issue is finally solved. It is fully working for me. No black screen issue. Backlight control working. Also, backlight level is being restored properly across reboots.
Don't have enough words to thank the awesome people who worked on it and fixed it.
Remove AppleGFXHDA.kext from /S/L/E. Keep it in a safe place. And then for audio use only AppleALC method. No Fake ID. The audio will work. The thing is the controller related. Removing GFXHDA sometimes gives kernel panics though. only sometimes. But it does bother me though.
@parasthakur37 you should delete this config.plist/Devices/Properties/PciRoot(0)/Pci(0x02,0) This is blocking the graphics properties from taking effect. And also in your config you didnt change gfx0 to igpu. Do that also.
Installed kexts to /L/E and also installed lilufriend. Did not change anything with the brightness issue. The ALS0 is showing in ioreg but i dont know what it is used for. We have reached the stage where brighness works more often.