Thats a good question... I honestly do not know what happens when voting power goes to 0, though it should regenerate after 24 hour... As for the payout, curators get a 30 percent cut or something, so that is why youre getting less than what it says the payout is
RE: PSA: If you are seeing value disappear from your posts right now, it is because Steem is experiencing a correction (dont freak out)