I do not know if here is the place to report it, but there it goes (if not, please can someone tell where it is for me to make a post there?)
GURPS Innate Attack Calculator is ignoring the -10% from the
"magic" limitation. When you select the limitation it does not apply to the cost or the description.
link for the game aid
http://www.sjgames.com/gameaids/gurps/g4innatecalc.html