highly recommend purchasing a ground loop adaptor from espressive-e instead. it works and is very robust. you can of course still build your own offworld from the files but we no longer sell them.
you can now order them, assembled and enclosed, direct from https://market.monome.org/products/offworld-1
this little dongle allows you to power a device (ie grid) from an external source (ie iphone charger) while passing the data lines to a host (ie module)
it’s also 100% open source: https://github.com/monome/offworld-1
if someone wants to build and sell these themselves, please do!