I just wonder how it can be that the game ends with 'I win' when a king on a5 is captured with a move from a9.
I am not sure what exactly you tried here, in particular, what you mean by 'king'. It should not be possible to have a King on a5; it should have morphed to a Royal Pawn when it got there.
Did you move the King to a5 through an illegal move? The I.D. allows you to play illegal moves, (if these are non-captures), but these are considered part of a position setup, and would never be subjected to promotion rules. They just move a piece from one square to another. So if you play Ke1-a5, it would not morph into a Royal Pawn, and stay a King. (But due to your choice of images, you cannot see that!) As a consequence you have not lost yet, and if it can the AI would capture your King and claim the win.
If I play, from the start position, Ke1-a4, switch on the AI, and then play Ka4-a5, it does claim the win. (A bit strange here is that the King appears to promote to an enemy non-royal piece; I still have to figure out what causes that.)
I am not sure what exactly you tried here, in particular, what you mean by 'king'. It should not be possible to have a King on a5; it should have morphed to a Royal Pawn when it got there.
Did you move the King to a5 through an illegal move? The I.D. allows you to play illegal moves, (if these are non-captures), but these are considered part of a position setup, and would never be subjected to promotion rules. They just move a piece from one square to another. So if you play Ke1-a5, it would not morph into a Royal Pawn, and stay a King. (But due to your choice of images, you cannot see that!) As a consequence you have not lost yet, and if it can the AI would capture your King and claim the win.
If I play, from the start position, Ke1-a4, switch on the AI, and then play Ka4-a5, it does claim the win. (A bit strange here is that the King appears to promote to an enemy non-royal piece; I still have to figure out what causes that.)