Does the material setting refer to the actual thickness of the material or something else?
I believe it’s only for reference sake. It doesn’t actually affect any settings.
It’s used as an offset to adjust your bed or z-height, if you have that capability.
It does, if you have the Z enabled and use absolute Z moves. It will move the Z to the specified height. Mostly for Emblaser 2 users, but works on other machines as well.