I have created a tool that allows flashing/erasing (among other things) of W600 chips:
https://github.com/vshymanskyy/w600tool
Feel free to use! This is based on some chineese docs and scripts I could find, but I have also investigated/implemented the proper command format so this script can be a starting point for further development.
For example, this enabled me to implement “set mac address” function.