I had the same Problem. The last line of my log file was:
A quick google search showed that the missing file is part of a shader pack:
GitHub - ac-custom-shaders-patch/sdk-shaders: Some of new shaders compiled for AC SDK (both versions) and vanilla AC
Some of new shaders compiled for AC SDK (both versions) and vanilla AC - ac-custom-shaders-patch/sdk-shadersgithub.com
Downloaded the latest version, put the files in the right folder and it worked.
At least for me. Hope this helps.
Ahhh yes thank you this enlightens the issue. Makes total sense. For 0.9 i applied that shader into some objects in the scene in order to make building lights for the night.
To anyone with these kind of issues try downloading the quoted package and drop the content of "new" folder into assettocorsa/system/shaders