koobas.hobune.stream
Imported 3d model makes the games view grey.
I saved a sketchup model as a .dae file so that I can keep the textures. After loading the model into the scene the entire game view shows as gray. When selection the camera, the camera shows everything rendering properly. Moving the camera around away from the model doesn't change anything. When I remove the model from the scene, (still in assets folder) the gray goes away. I tried opening the model in a different application. That also went gray in the game view. I even closed the programme and reopened it. Nothing changed.
Thank you for any help you can offer. 
Make sure front faces are facing the camera inside Sketchup (See your model in Monochrome mode). Most game and render engines ignore backfaces.
Note that you can directly import Sketchup (.skp) (version 2015) files to Unity (and it does the conversion automatically for you). Other file formats can keep the textures as well, you're making something wrong probably.
I had the same issue.
I've found a model for a prototype I'm making on a web and as soon as I've added it to the scene, the Game View turned gray.
It took me good 20 minutes, to figure out that this model had it's own camera within the rig, that was rendering over on the Main Camera.
I just opened the mesh in Blender, removed the Camera, exported it again and now there are no issues. Stupid bug, but it got my head spinning a little. I was thinking that maybe there are too many vertices for a scene, or something is wrong with the geometry but it turns out it was that simple.
