Models in scene and game window look gray

My models appear in the scene window and game window after being built and run as grey without any of the applied textures. I have set up the materials for each object including a bump and diffuse and they show up fine in the preview or if I click the little sun icon at the top of the scene window. Why aren't they showing up in the preview window or when the app is built and run? Please help!!!! I'm completely stumped on this. The models were developed in 3DS max 2011 and imported as FBX files. Thanks