uninstalled, rebooted, reinstalled, terrain files added, stdshape was already installed and still nothing 
How did you find out writing to invalid memory location?
Check that stdshape file size. Usually ya go past video settings and then DL shapes. I’m not sure we’re making it past or even to video setup
White screen is usually video or monitor related. In my case it was trying to read what wasn’t there. But if you have shapes and no change I’d be looking at video settings to make sure they’re in line with your monitor capabilities.
Again, process of elimination
Also in Win11 I think there is video troubleshooting app.
You can also look into Event Logs