can't render in blender game engine


I’m a freshman in blender, hope someone can give me some advice

I’m trying to make a sky box by using UV sphere, and I can achieve it in blender render engine by mapping the sphere into a sky image, however when I trying to do the same thing in blender game engine, I can’t see anything when I start the game?

Attach or link to your blend file so others can see what you are doing. Make sure you pack any textures in the blend (File / External Data menu)