The circuit description comment also needs to be dealt with:

I'm not sure what the best approach is. The associated tutorial should be considered (of course it can be updated as needed).

Most of the examples are doing the same hardcoded pin 13 thing as this "PhysicalPixel" example was using. The only exceptions which are usingLED_BUILTIN:

• Blink (tutorialhere)
• BlinkWithoutDelay (tutorialhere

Those might serve as a useful model for how to proceed to take advantage ofLED_BUILTIN in other examples and tutorials.