Models from SketchUp aren't loading properly.

I imported a model I created in SketchUp into UE4 and most of it turned out well, however, ethere were two things that didn’t work out. The first is that 4 walls, 2 ceilings, and the floor are only visible from the outside. The second is that (I am not a pro with either app so I may be getting this all wrong) things that I thought were movable such as a door and a fan are not movable so far in my progress on this project. Please help! Thanks! Let me know if any more information is necessary.

Now everything looks weird as well…