Hello everyone, I've set a simulation in Houdini in which a bunch of megaphones are falling from the sky. I have a background sequence both set in the cam viewport and the render view. I do have two problems now.

1st - I do have a ground plane set for simulation purposes and unchecking visibility in the node editor won't make it disappear. It is still there, why?

2nd - I have put a grid to be used as the floor, and despite it has a shadowmatte material applied to it, in the render view i still see, not just the shadows (which i don't see but that's not the issue), but the entire object is black, as no background was set in the PBR Render view… What is happening? Can you help please? Thanks…