Thanks for your feedback! To answer each point:
1) I didn't realize that the white promotion was not working, I guess something broke between my last test of that part and the current release.
2) This is something I didn't thought at the time, and considering how the code handles the game, I doubt it could be added, because the game doesn't keep track of the movements history.
3) Making the animations optional is a nice idea!
The thing about this project is that it was made for a jam in 2020, so I never thought about keeping the support for it. Also, currently I don't have the code for the game in my pc (hopefully it is located in some hard drive backup).
So I can't make any promises of improving it, but if I have the time (and I actually find the source code) I'll try to at least fix the white pawn promotion bug.
Again, thanks for playing it and for providing feedback!