I would have been very reluctant to play 13.c5, as it leaves the d5-square firmly in Black's hands. I'm wondering about how 13.Red1 would go...(13.Red1!? Qxb2?! 14.Rab1 Qxa2 15.Rxb7 Qa6 16.Reb1 ... Now there's an open file for you, with White's rooks firmly ensconced therein.

No, I'll annotate the rest of the game in due course - it was over 50 moves long!

That the reply 13...Qxb2 is not a good move is not due to 14.Reb1 Qa3 15.Bxh7ch Kxh7 16.Qxa3 ... on account of 16...Bxa3, and Black wins. However, after 15.Rxb7 ... Black would be getting the worse of it. I'm guessing Black played 13...c5 here?

My pick would have been a strike at the centre: 13...c5. After 14.d5!? exd5 15.cxd5 Bd6 16.Bxd6 Qxd6, Black would have secured a Q-side majority, and left White with an isolated centre pawn on a half-open file. White's slightly more active piece deployment would have kept the situation roughly even in the resulting position, methinks.

It turns out that White could have kept that b2-pawn as bait. For instance: 14.Rad1 Qxb2? 15.Rb1 Qa3 (NOT 15...Qxa2 16.Ra1 Qb2 [...Qb3; Bxh7ch] 17.Reb1 trapping the queen) 16.Rb3 Qxa2 17.Rb1! and the Queen is not going to escape (...Qa3; Ra1 Qb4; Reb1 etc)! There would have been a huge dollop of poison on that wee pawn!

You might be being over-critical here, Charles. The upside is that the BQ gets shovelled off into a corner and out of the action for quite a while. But maybe it ought to have waited a move or two. White could probably have launched a bayonet attack against the K-side with 15.g4, threatening g4-g5 and h2-h4-h5 etc. Once the knight got driven off f6 (...Ne8), THEN c4-c5 would have driven the Queen out of play and the attack might proceed. So the idea seems OK, just mistimed.

How is the Queen to get back into the action?

At the moment d5 is a weak square for me - a lovely square for him to put one of his knights - but if I can exchange it off, and he takes back with a pawn, it is not so good for him....

This is the logical follow-up, but I was looking more to Ne4 as a possible continuation.

I can surmise only that he intended to redeploy the bishop to g7. White can still look to attack by g2-g4, here.

...and were Black to play ...Be7 now?

18.Bf4 was definitely worth a look, having induced a slight weakness on Black's K-side. I think the bishop's interdiction of the centre and Q-side dark squares is more inconvenient to Black than is the pin.

Or, it is arguable that Black has induced a misplacement of White's dark-square B (DSB). That is supposing it IS misplaced. Bg3 will get it back on the useful h2-b8 diagonal, but then it blocks the g-pawn, which ought to be looking at a fine military career ahead of it.

I prefer 19.Bg3 here, or maybe 19.Ne4. I still think White has promising prospects on the K-side.

Another idea was 19...Nf8, attacking the backward d-pawn, and threatening ...Ng6 to attack the h4-bishop.

Erm... You know this bishop sacrifice you mentioned earlier...? 20.Bxe6!? fxe6 21.Rxe6 Nf8 (say) 22.Rxc6 Rxd4? 23.Bxf6 Bxf6 24.Nxb5 ... and White emerges with a distinct edge after 24...Qd7 25.Nxd4 Qxd4 26.Rd1 - R and 3 vs N and B.

This is a serious mistake. Much better was 20...Nd5! with the ideas [a] 21.Bxe7 Nxe7 or [b] 21.Nxd5 Bxh4 22.Nc3 Bf6 23.Qxc6 Bxd4 24.Nxb5 Qxc5 and material equality has been retained. The resulting position looks difficult to call at this point.

Why not 21.Qxc6 at once? After, say, 21...Rac8 22.Qf3 b4 23.Nb5 Qd7 24.Rad1, Black doesn't look to be having much fun. This might have been an(other) opportunity missed, possibly.

21.b4 was worth a look.