Problems with Sketchup 2019 walls and floors

Thanks all of you guys. Just a last question.
I have an architect that will work the Sketchup model for me, so I only have to import it, but I don’t know how to use Sketchup at all.
What considerations and warnings I have to tell to my architect, in order to have a perfect and smooth transition to Shapespark without any errors.

So far I know that the faces of all furniture and walls have to be facing outside, but there’s any issue with materials or something like that?

Please give me the advices for a perfect transition to Shapespark, it will help me A LOT.

Thanks again, you’re all great