I built the sample Secondary USB Bootloader application (no changes) for the MCB1700 board and flashed the bootloader to the board.
I connected the board to my Windows 11 system (using the USB-B connector on the board). Held down the joystick button and pressed RESET.
Windows "This PC" shows a USB device but nothing is shown as being mounted:
So what did I do wrong? The joystick switch works OK and the earthy side of the switch measures 100 ohms (R81) to ground.