Just to make sure, when you're on the default watch face (and the bangle touch screen is not locked) you can't get to the launcher by pressing the physical button? If you can you should be able to navigate to the settings and do a factory reset.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Just to make sure, when you're on the default watch face (and the bangle touch screen is not locked) you can't get to the launcher by pressing the physical button? If you can you should be able to navigate to the settings and do a factory reset.