I just had to put the file in the right place and try using the Defensive Spin. It lowered my AC by 5 on level 5, so it works.
Still, I think the Defensive Spin will only become useful for this "kit" around level 10, when it'll finally outpace superior armor when used. I guess it's diifferent for the Blades, since they can't wear armor if they want to use spells.