Skybox does not appear in AR


I have a problem using the Skybox in my AR Scene ( I used the AR Template ). I want to use the SLS Specified Cubemap to get reflections on my material (Or at least some lighting). In the editor it looks totally fine, but when i run my application its gone.

The second problem are missing Shadows, which I could not get to work. There no shadows at all ( Not in the editor or the Scene itself).

Do you have any thoughts what should I test ?