Well, this is a bug I found. Not much really, but a bug nevertheless. The program claims I allowed check at d2 or gave my queen away. As you can see, neither is the case. Heck, my queen can't even be attacked without black losing material. The main reason I played this move was to keep the rook off the D file, anyway.

This should be corrected now. It has been changed so that the move Bd5 is classified as an alternate correct move as it blocks the d-file and prevents any entry from black.

Thanks.

Any solution found?

 

What do you mean?

On another note, I believe I have found another minor error. As you can see here, White is in check. He cannot move out of the check, or capture the checking bishop. As such, he can only block. Let's see the five possibilities.

Qd5 Qg7#

Qe6 Qg7#

Qf7 Qh8#

Rf7 Qh8#

Bd5 Bxd5 Qxd5 Qg7#

Solution move: Qxg6 Qg7 Qxg7

Of course, the solution move is quicker (assuming black plays correctly), but I like these other mates where the queen does not capture better.

 

Yes, thank you for finding this. The move Bc4+ has been added as an alternate correct move now.