I noticed that I could see the shadows in the editor, but they won't be rendered in my .exe build.
Tried changing all the light settings I could. In the objects themselves, the light sources, the quality settings, nothing worked.
Then I tried a new scene with a plane and a cube, and shadows worked. So I went back to my zspace scene, and I disabled the ZCore component. Shadows worked again.
Has anybody experienced this before? I don't know that to try next.