Setup rtx for world of warcraft 1.12.1
Step 1. Download rtx runtime, i tested 0.4.1 and it works, find it on their github under releases.
Step 2. Download SteamDepotDownloaderGUI, also on github, any version
Step 3. Download portal rtx with these parameters (you need a account with portal owned), appid 2012840 depotid 2012842 manifestid 4888596585209550811
Step 4. Now go into the folder that steamdepotdownloader made and take from bin D3D9.dll and put it in the game directory, and from bin/.trex/ you want NVRemixBridge
Step 5. You should be able to launch the game now!