Colin now missed the best continuation and went on to lose the game. Can you see it (answer below).
Answer: 17...Qb6+ 18. c5 Bxc5 19. Kf1 (only move). Colin now suggests 19... Bf2, although with best play (20 Nc4!), White can probably survive. Perhaps the best move (after 19. Kf1) is ... Bd6, renewing the threat on f2 and preventing White's threat of Bf4+.
But it's a complicated position and further analysis may reveal a better solution. Can you help?