Also, the FEN was inaccurate. It gave me this: 4k55K3.
As you can see, it omitted every piece except the King.
You might have forgotten to press the 'Start Position' button after seting up the pieces. The Applet allows you to put more pieces on the board after fixing the initial position, which will then be available as promotion choice in the Diagram / GAME code you produce from it without being included in the initial setup. If you don't press the button, the initial position stays what it was when you opened the page, i.e. just the Kings.
You might have forgotten to press the 'Start Position' button after seting up the pieces. The Applet allows you to put more pieces on the board after fixing the initial position, which will then be available as promotion choice in the Diagram / GAME code you produce from it without being included in the initial setup. If you don't press the button, the initial position stays what it was when you opened the page, i.e. just the Kings.