590: 38-33 43-38 26-21 is winning as well

Also 644: 35-30 34-29x30 33-28 27-21 and variation are winning.
I recognize that the given solution for both this one and 590 are a bit better, but both alternate solutions are easily winning as well

Puzzle 4233: too many winning combinations, e.g. 2631 1621 1822 2329 19x46 is not really wrong, but is indicated as a mistake. also 2631 1621 2430 is winning.

lidraughts.org/training/4233

I believe 27-43 works in this puzzle.

lidraughts.org/training/753

21

Puzzle 537: 33-28 43-38 42-38 36-31 39-33 is also possible and winning.

lidraughts.org/training/537

Puzzle 5973: also 1721, 2328, 2429, 19x48 is winning.

lidraughts.org/training/5973

4

495 - 6.49x38

Puzzle 487: the solution 30-25 (26-31) 37x17 (24-30) 35x24 (20x40) is winning easily as well, but considered wrong.

lidraughts.org/training/487

4

lidraughts.org/training/frisian/278 has a wrong solution

Puzzle 590: there is another combination, 38-33 43-38 26-21