A short, hard puzzle! =)
Nice, and I did find it :-)
But I don't see the continuation after 2.Kf1. Still, this is the best try black has.
you are correct about K-F1, but we'll just assume whites polite enough not to see a queen and a rook sac =)
Kf1 and it doesn't work, yeh, and also Qd1+ Kxd1 and the rook just keeps checking until Kf1 and Kb2.