I have a problem- I just completed the Biel International and my only loss came when I played black against the Israeli GM Maxim Rodshtein (2637 FIDE). I came into the early middlegame with a slightly worse position, but I don't think it was anywhere near lost. I blundered later on in the game, but by that point my position was already a bit sketchy as I had been counting on a tactical sequence working for me that just completely didn't. In any case, I'll open it up to the members of the chess.com community to try to tell me how I could have played better. One FYI- I have a very powerful computer that can simultaneously run Houdini and Firebird on 8 cpus, so if you just want to spout computer lines it probably won't help me! Human-created plans, on the other hand, could very well be useful.
The first moment I think was largely critical was on move 18. I felt that I should move the d7 knight to contest the dfile, but to b6 or e5? e5 is surely a more active square, but it may compete with the other knight for it and b6 pressures the a4 pawn and the slightly weakened white queenside.
I ended up choosing Nb6. I had foreseen that after Nc5 I would have to capture it because Nxb7! is a very strong threat, but it didn't seem like such a problem after Rxd4 Rxd4 Bxc5 Qxc5 Re8! threatening both Rxe2 and preventing Qxa5 because of Re5 (which will inevitably kick the queen back anyway). The next critical moment came on move 23.
I had 2 main candidate moves here: Nd7 and Qc8. The point of Nd7 is to improve that lousy knight (while incidentally threatening Rc5) and the game could continue with Kb1 fxg3 hxg3 Nc5 intending Ne6 and Rc5, with a strong reorganization. I ended up playing Qc8 though, intending Nd6 Qe6 Kb1 (gxf4 Nxf4 didn't bother me) Rd5!, trading off the rooks as I felt his was better than mine and Bxd5 obviously fails to Qxd6.
Ultimately, I blundered the game away a few moves later with Qh3??, overlooking that after Qd6+ Ka7 Qd4+ Ka6 would not be quite as strong as I anticipated. Instead I had to return to b8 and after Qd8+ Ka7 Qxa5+ would obviously end my suffering. I elected for Qc8 instead of Ka7, but still Qxc8+ Kxc8 Nd6+ Kc7 Nxf7 left me helpless and I resigned a few moves later.
The complete game is as follows: