BTW, my hardware has arrived, but I’m currently stuck on being unable to test my changes, music.playInstructions appears to hang the Adafruit PyGamer even when using the original code. I filed https://github.com/microsoft/pxt-arcade/issues/2423 to follow up on that.
I haven’t gotten hiddmesg or WebUSB working yet in my CLI setup, so I don’t know if it’s reporting any error messages. I’ll poke around some more if I find time.