I've made it so that talking to the statue unlocks the Dark Storm skill if the needed Master count has been reached and you talk to the statue -- doesn't matter what it says. It's a skill for Rok, Slith and Karas. I'm not sure if it's still all that useful if you're nearing the end of the game.
Did another quick update adressing the speed debuff and the bonus turn star. Heavy stops after battles, but Light doesn't. Loading the game resets the light/heavy status now. The bonus turn star also saves its status now.