Solution
1.S*2a 2.Gx2a 3.B3d+ 4.K2b 5.+B2c
1.S*2a 2.Gx2a 3.B3d+ 4.K2b 5.+B2c
1.R*1c 2.+Bx1c 3.R2a+
1.P*2d
there’s no way to prevent Pawn promotion.
1.P*2c doesn’t work because 2.B1c
1.P2c+ 2.Gx2c 3.P*2d
1.N*2d 2.K1a 3.B2b+ 4.Gx2b 5.P*1b 6.Gx1b 7.Nx1b+ 8.Kx1b 9.G*2b 10.K1c 11.N*2e
1.+R1d
1.G*1a 2.Kx1a 3.G2a 4.K1b 5.R*1a
1.N2b+ 2.K4a 3.G*5a
1.+R1c 2.Gx1c 3.N2a+ 4.K1b 5.+B2b
1.+B1b 2.Kx1b 3.G*2b