Solution
1.G1a 2.Kx1a 3.+B2a
1.G1a 2.Kx1a 3.+B2a
1.+B4a 2.K2b 3.+Bx2c 4.Kx2c 5.P*2d 6.K3b 7.G*2c
1.N2e
white can take the Rook on 1a.
the 5b-Rook controls : 1b-square and 2b-square.
the 5d-Bishop controls: 2a-square.
K8h
K7i
1.B3b+
1.B5c+ 2.Gx5c 3.+R3b
K9i