I just remembered I totally forgot to come here post the solution. My apologies but better late than never :).
The main interest of this position is the apparent mutual zugzwang soon appearing after 1.d4 Bd6 2.Bg6, when playing natural moves and bringing the white king to f5 (in the position white : Kf5, Ra8, Bg6 pawns d4,d5,e6/ black : Kf8,Re7,Bg3,Ne8).
In that position If black is to play (which is the case ine the soçlution below after 13.Ra8), black loses very quickly (1...Bh2 loses the possilibility to play bh4+, so 2.Bxe8 Rxe8 3.Ra7 (threatening 4.Rf7+ followed by 5.Rd7 and the d pawn will be able to move to d6)3...Rb8 4.Kf6 (and bh4+ not possible anymore with the B on h2).
On the other hand, with white to play (which would be the case in the solution below if white would chose to play the natural 6.Kf5), it's much harder to figure out how to win. The triangulation manoeuver requires to bring the white king to g4 and the white bishop to h5 (which aren't very naturlal ideas), before trinagulation with the rook (although the move order doesn t matter, you can olay 1.Rc8 Fh2 first, then bring the king to g4 and then the bishop to h5, or play Kg4 first or Bh5 first), but the traingulation manouever itself stays unique and the only way to win (just interversion duals).
I'll just put the solution as is, I'll try to go into more details if some things aren't clear :
1.d4 Bd6 (i)
2.Bg6 Bb4
3.Ke2 Bd6
4.Kf3 Bc7
5.Kg4 Bh2! (ii)
6.Bh5 Bc7! (iii)
7.Rc8 Bh2! (iv)
8.Rd8 Bc7
9.Ra8 Bh2! (v)
10.Rc8 Bd6
11.Bg6 Bh2
12.Kf5 Bg3
13.Ra8 Bh2
14.Bxe8 Rxe8
15.Ra7 Rb8
16.Kf6 Rb1
17.Ra8+ Bb8
18.d6 +-
(i)1....Bxd4 2.d6! Rxe6 3.d7! Bb6 4.Bf5! Re7 5.Bg4! +-
(ii)5...Bd6 6.Rc8 Bh2 7.Kf5 Bg3 8.Ra8 +-
(iii)6...Bd6 7.Kf5 Bg3 8.Bg6 +-
(iv)7...Bd6 8.Bg6 Bh2 9.Kf5 Bg3 10.Ra8 +-
(v)9...Bd6 10.Kf5 Bg3 11.Bg6 +-