No you do not have to figure your coconut milk in as part of your 'oils' as it would be considered as part of your liquid. That is the one thing I dislike about
lye calculators is they all say 'water' when it should say liquid because many do not use water, but other liquids instead.
However as far as superfatting, I am not sure what the rate should be and what
lye calculator to use.
But I am interested because I'd like to make a bar of soap that lathers in salt water....... But won't be harsh on your skin.
So i'll watch this one with interest.