First of all u need a clean copy of the game . !
Clean copy means there is not files left in steamapps/common/DOOM 3 BFG Edition
-if you alredy played the game go to : C:\Users\XXX(YOURNAME)\Saved Games\idsoftware\Delete folder DOOM3 BFG

Download and install DOOM 3 BFG Edition from steam. Dont push PLAY button yet.

Download: https://github.com/MadDeCoDeR/Classic-RBDOOM-3-BFG/releases/tag/1.3.2-BFA_patched | x64-windows-linux.zip

Download: https://github.com/MadDeCoDeR/Open_Platform/releases | OpenPlatformWithSteam

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After downloading this things: Extract all files from x64-windows-linux.zip to your DOOM 3 BFG edition - replace the files if needed

Now open (Open_Platform.with.Steam.zip) Win64 and put OpenPlatformx64.dll to base folder (C:\Program Files (x86)\Steam\steamapps\common\DOOM 3 BFG Edition\base)

And steam_api64.dll to C:\Program Files (x86)\Steam\steamapps\common\DOOM 3 BFG Edition

Now create a text file in Doom 3 BFG Edition Directory (C:\Program Files (x86)\Steam\steamapps\common\DOOM 3 BFG Edition\) named steam_appid.txt and put there the number 208200 (just this number and save it)

Now delete DOOM3BFG.exe or rename to something else DOOM3BFGOriginal.exe.

Rename DoomBFA.exe to DOOM3BFG.exe.

Now u can press play from steam but dont do anything just boot to menu dont try to open console or something. (you can skip intro by ESC key)

Go back to C:\Users\XXX(YOURNAME)\Saved Games\idsoftware\ open DOOM3BFA folder /base DBFAConfig open with notepad find the line (CTRL+F) bind "F12" screenshot - DELETE THIS LINE and save.

Now its done u can screenshot and achievements will be not disabled if you follow the steps it will work .