The soft_env_sphere box can be used only with a map to define the reflected environment of the surface. The soft_color_2D box is used to give the location of the picture file to use as the map. The EnvironTex box defines how that map is used to create the reflection. The ROT button can be used to rotate the reflection about the object. These four boxes need to be used in conjuction with one another. This is the SoftImage implimentation of a Mental Ray 'environment shader':