Hint for clue #1

There are three game boards hanging on the wall. The space between them forms a triangle. That’s the area you want to use to solve the clue. To do that, think of the circles on the clue as stops on a map or moves on a chessboard, perhaps starting with the only circle that looks different than the others. What stops would there be along the way if you thought of each one in spatial relationship to each other?