Skyboxes: So far, the Sphere-From-Scratch trick isn't working

I decided to give skyboxes a shot for this application. For OpenGL, the cubemapping process is fortunately simple and manageable, but regarding DirectX's DDSTexture loading code (Currently using a large cpp file that automatically loads from a file), it's difficult to figure out whether it's loading the cubemap properly. A certain set of tutorials I'm following detail a sphere automatically created on the fly, and I managed to get the skybox settings properly set with setting culling to none and making the skybox the furthest object away by swizzling (xyww) and setting the Depth Stencil state, but the product...eh.

There's a sky showing in a large, jagged half sphere that doesn't cover the entire set. In all honesty, tomorrow I'll probably create a sphere or cube from Blender and load it this way; it'll limit the variables of this situation. If it's the texture...ugh. Let's hope it's not the texture loading code.

I have Jockum Skoglund to thank for the lovely skybox from Open Game Art. Thank you!