Keys "s"=save "l"=load "b"=back once
My assistant Tom Demark MD remembers that when he was in third grade in Independence, Missouri, his teacher Mrs. Graycheck taught the class to play chess, and organized a tournament. Tom was the strongest player. In this classroom, pawns promoted only to pieces already captured. (If there was none available, I have assumed that the pawn never promoted.) This must have been implemented to prevent borrowing from other sets, which would have left some with missing queens.
These are simple illustrations rather than strong opponents.
Bug reports? -- Thank you! Keep them coming!