https://steamcommunity.com/app/244210/discussions/0/3824163953451160286/

So if you want to just play the base game then you can launch using GE-8-11 and it will crash after it loads all the back end stuff, don't rush it, just load it with GE-8-11 and let it crash itself. It has to build a file structure and download .NET framework. After that the second or third boot it will work.Now if you want to use CM or CSP, follow the guide I posted. Then in addition I use CSP 1.74 because it was the most stable. DO NOT SKIP THE dwrite fix before installing CSP. I have my game installed on a second HDD so I had to change some of the paths. If the Steam login doesn't work by linking it, just copy the raw file to the same place you put the link and delete the link. Also turn off Hardware Acceleration in UI in the CM settings, it's down the bottom and it will stop you getting black boxes upon exiting sometimes. The game runs beautifully and fully maxed out my rig still gets 100fps. I had to install like 6 times and take notes until I figured it all out and then I found the guide I listed, the other guides are just so full of stuff you don't need. Follow the guide carefully and just use your brain and it isn't that hard. The CSP makes the game look absoutely amazing! If you tried to install it before and borked it, make sure you uninstall the game and remove the steamapps/compatdata/244210/pfx folder and delete any leftovers in the AssettoCorsa root folder so there is a fresh start before re-install and READ THE GUIDE FULLY BEFORE YOU START. The little details make all the difference but this guide turns a Proton 5.10 with 1,000 steps into about 5 main steps. Give the guy who wrote the guide on Steam an award, he got it right. I just got lucky from keeping notes and multiple attempts.