A22: No, to my knowledge, there is no official ruling on that. However, I think it's safe to assume that if a non-humanoid creature has the proper body type for a slot, then it should be able to use it. (For example, if a creature doesn't have a neck, it can't use a neck slot, but if it does, even if it's non-humanoid, then it should be able to use a magic necklace)
Planetouched isn't official. It's the fan category for Ifrits, Slyphs, Undines, Oreads, Aasimar, and Tieflings, since that was the term used in 3.5.