For 3.16-5 Beta ED - that's a bug in my script. That second if statement at line 576 should be indented to run only if the previous one is true.
For 3.16-4 Beta ED - it looks like a shader compilation issue.
You could try installing DXVK 0.94 on 3.16-4 Beta ED. You can do that with 'winetricks dxvk'. If that doesn't help, you might want to share what graphics card and driver version you are using. But make sure you are meeting the Proton Graphics Drivers Requirements.
Fixed it by downgrading my graphics driver to mesa-vulkan-driver 18.0.5 from the ubuntu repository. I had version 19 from the oibaf ppa. Thanks for the help.