DX11 is now the default on the new build. You can go into game prefs in Steam to manually select DX9 IIRC.
Right-click on the rfactor 2 title in your library and click on properties. A new window will appear. Click on the Beta tab and select the -v1109-dx9 option.
As soon as they release info to add screen overlays or add them themselves, I'll be there. Until then, I'm deprecating