Hi. I'm testing out Mesh. I created the basic frame structure of a house and exported it to .dae. I finally was able to get it to import but I'm not sure how I can make it able be walkable. Meaning walking into the building. Basically its a solid cement building with cutouts for doors and windows. When I upload it consider the mesh one object(not a object with holes) so what could be the cause? I'm using Blender and exporting the structure as a collado file. I'm not worried about texture until I know how to at least get the structure to work.