you can use the HeightMultiplier parameter to squish it a bit, but don’t offset Z, it does really bad things. If you’ve made a material instance, if you edit it, under Parameter Groups -> Sphere you’ll find all the exposed parameters. If your mesh is +/-Z the sphere will distort, it’s best if the Z of your mesh is generally 0+ (with -Z becoming really odd).
And yea, the offset parameter is RGB -> XYZ
Finally the Param MaskRadiusMultiplier looks to be really good around .407