I am one of the project creators. This was a last year project in our company innovation week (http://piweek.com/) but it never become a large project because it is hard to make changes to the

Inkscape UI if you are not a developer. So it was just a first draft to see if inkscape developers will like our ideas and we could help them to improve the UX/UI for future releases. It did not work and we just left the project.

The useful links you are looking for are: http://piweek.github.io/rethinkscape/ Docs: https://github.com/PIWEEK/rethinkscape/tree/master/docs Mockups:https://github.com/PIWEEK/rethinkscape/tree/master/mockups

Thanks!