43.h4xg5! pawn exchange was the way to go. Then after 43.....h6xg5 comes 44.c5..b6xc5+ 45.Kxc5..g4 46.Nf4...... and white has 2 passed pawns to Q and black will have to sac his bishop to stop one!

I think you should take here

Still not too late to exchange! 44.hxg5..hxg5 45.c5..bxc5+ 46.Kxc5..Bd7 47.Nd5..f4 48.Kd6..Bxb5 49.e6..Bb8 50.Ke5 and white wins

I think the last moves of the line should read 49...Be8 50.Nf6 Bg6 51.Ke5! Kc7 52.e7 Kc6 53.e8=Qch Bxe8 54.Nxe8 Kd7 55.Nf6 (Kf5 also wins, but I'd rather make it certain).

Nd5 then after Bg4 Nf6 keeps white in front!

After 45.Nd5,Bg4; 46.Nf6,Be2; things are not clear. Black is threatening g4+f3, while c4 also hangs

Be4 is answered Kxe4. Perhaps dynamic_dv meant Be2, threatening g4

Mistake by black? Be4 would give him the draw. sorry, I meant Be6, preventing white playing e6

White still wins with 47. e6!

47...g4 doesn't quite work. If 48.Nxh6? then 48...g3! does force the draw, but 48.Ke4! f3 49.gxf3 gxf3 50.Ke3 Bg4 51.Nd3!! wins (Not 51.Nxh6 Be6 52.Kxf3 (what else?) 52...Bxc4 and 53...Bxb5 secures the draw for Black).

48.Ke4 keeps white in the hunt!

It seems that to retain winning chances, White has to time his capture on h6 to exactly the right moment. However, it is not clear that even 48.Ke4 will win: 48.Ke4 Be2 49.e6 Kc7! (Not 49...Bxc4 50.e7!) 50.Kd5 Bf1 51.Ke5 Bxc4 ...

Move 48 was your last chance for the win Charles, barring any mistakes by black.

Odd, how the bishop suddenly dominates the board.

Excellent defence, showing that your idea to win the miserable pawn h6 was wrong. You really had a lot of ways leading to the wictory, but not that.

I think Black's whole plan of defence was predicated upon freeing up the bishop and mobilizing his K-side pawns, even at the cost of falling a pawn behind. Probably White ought still to have won, but I rather think White's last best chance went with 44.h5? (instead of 44.hxg5). After 48.Ke4 I'm inclined to think Black has enough counter-play to save the game.