Bonus Chapter HOP not responding

I'm currently in the Bonus Chapter and attempting to play the HOP on the King's desk. The first task is to find a king chess piece.

I've found it, and keep tapping on it, but there is no response. All other selections like Menu and Hint respond as usual.

Has anyone else had this problem?

I just realized there's a better discussion for this. I'll post the question there. Sorry!