hello,
I think there is a bug with shadows mode: realtime.
example:
import a model
Z move your model in the scene, to see his shadow on the ground
move the cursor shadow quality settings in the window.
everything is ok
but now:
try changing the material of your model of thin film.
ok, you can see his shadow.
move the cursor shadow quality settings in the window.
shadow disappears ...
ok
now,
use any material on your model.
shadows no longer appear on the ground ...
Antoine
You will need to force a refresh of the shadow calculation. Slightly nudge the environment and the shadow will update. Or as you did, move the quality slider for shadows again, and the shadow will update.