I'm not really seeing the problem here. I'm assuming the textures are mapped on the sky reversed, it should not be a problem. However, where the game gets the "cloud1" and "cloud2" textures, is beyond me. As for the sky "cutting off", that is because your texture for the top sky plane is a black starry sky which does not blend at all with the light sky on the other planes. On the other hand if you are referring to the city buildings being under the horizon, that's how skyboxes work. Half of the image is mapped under the horizon, half of it above. Your only problems are crappy low quality textures and the wrong top sky texture. Nothing technical.