Hallway

I’ve used the game engine to do a walkthrough of a house. Modelling it was eay enough, putting in windows and all, now jsut have to put some furniture in. Only problem is when you go to play game and actualy try and walk around everything is just a blinding white for the walls and just plain slabs of colour on the ceiling and floor. Even when i jsut try to render the image it doesnt work. Ive tried putting textures on the walls and they dont even show up to try and break up the white, removing the lights doesnt help either. The colours jsut wont work, and it doesnt matter how good the modelling is if the colours are all crappy. Also why does the background image just randomly disapear and then not come back again? Im trying to model in the right place for the windows using a floor plan but my floor plan background image has gone. even reloading the image again doesnt bring it back. why does this happen?

Can you post a screen? In the game engine make shure you windows view is set for shaded or textured.