McIlroy finished with a 2-under 68 and is in eighth place after the third round.
Kingston started with a double bogey on the first hole, then made six birdies the rest of the way for a 10-under total of 200.
David Lynn of England was a shot back in third after a 68.
Paul McGinley of Ireland put himself in contention for his first title since 2005 with a 64, matching the best round of the day. McGinley joined second-round leader Simon Dyson, Niclas Fasth and Alexandre Kaleka in a tie for fourth at 8 under.