Though I posted this about the fog not being the right color, models aren't either. The sky in my clouds texture should be true blue, (0, 0, 255), but instead, it's appearing as something like (0, 0, 202). Would you also fix this in addition to the fog color stuff? JCL stated and confirmed the bug with the fog and the same thing applies to models.

Textures in the engine look different than in a paint program, due to the lighting.

yeah check your ambient, albedo, world lights and dynamic lights. by making the ambient 100, albedo 0, and bright lights, your models will have at least the brightness of what you make them in your paint program,and without dynamic lights, you probably won't have the shaded effect on your texture that will make the lighted side brighter and the shadow side darker.