I am having the same issue with shadows. I have checked every setting I can. They've worked since I've upgraded to CA10 and I haven't changed anything. No, I am not using the Beta version. I'm not sure if there is a setting I am overlooking, I know some of the menus have changed since the upgrade, or if it's something to do with my video card.
This is a drawing I am working on now. I have erased all of the CAD details, dimensions and text only to reduce the file size. The shadows do not work in any file that I open up.
R-2577-1_Shadows_Test.plan