Shadows issues with LWRP - ShaderGraph - 2018.3

Hi everybody...

Really, I'm so unlucky with the new LWRP and HDRP pipelines ! Or Unity becomes really buggy...? (I know it's still in preview but... :'( ).

I downloaded the Island demo (https://blogs.unity3d.com/2018/10/05/art-that-moves-creating-animated-materials-with-shader-graph/) and with the last version (2018.3), I can't see all the shadows


Background: With the shaders used for the demo.
MeshRenderer.CastShadows = true


When I click on their shaders, always this warning:



I didn't modify the original shaders.
Just read them.

I updated the LWRP & shadergraph packages.



After my problems with the HDRP (https://forum.unity.com/threads/201...ok-of-the-dead-and-tree-buterfly-demo.605515/), it becomes boring :/

Thanks a lot in advance if you have any clue...