It’s really not ideal. Your kickstarter page should have been more specific about the need to essentially modify your derailleur if you don’t have threads (which many modern derailleurs don’t).
In this thread you say “you don’t need to wind it all the way in”, yet in the pictures above it is flush with the deraillur body - if i had known that before and I didn’t try wind it all the way in, it likely wouldn’t have broken.
Maybe if you’re winding it in to a derailleur body with softer aluminium it might be less likely o break but something like a higher end Shimano or Sram derailleur is pretty solid.
With the lead time and delays with this product there should have been time to produce a comprehensive instruction document for installation.