Dynamic Light placed inside of a Dynamic Static Mesh doesn't pass through the geometry. The static mesh is not double-sided.
It appears that in Unreal 4.16 one loses the ability to place movable light sources inside movable shadow-casting objects.
This unfortunately, breaks lighting for many scenarios: In one example case of mine, I have a spotlight inside a (shadow-casting) flashlight mesh. Both are moveable. The flashlight can no longer shine light in my game (worked fine in 4.15).
I could of course disable shadow-casting from the flashlight mesh, but the lack of shadows is very noticeable when placed on a surface like a table or the floor.
Results: In 4.16+ the light will no longer pass though single-sided geometry
Expected: For the light to pass though
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