You receive the BREASTPLATE PIECE 3/3.
Repair the net with the ROPE (purple); take the NET (K).
Insert the 3 BREASTPLATE PIECES into the slots (L).
Play the mini-game.
Casual solution: M, P, N, Q.
Hard solution: N, M, O, P, Q, O, M, N.
Take the MONOGRAMMED KEY (R); connect the THREAD to the needle (S), take the NEEDLE AND THREAD.
Walk down, move forward.