I've only ported this mod to 0.15, in case anyone would like to use it. If there is demand, I might build upon it.
The Long Nauvis is an infinite stream of parallel worlds that are similar to Nauvis and that can be reached via a device called a 'Stepper'. The Stepper device allows you to step into an 'adjacent' world, a step along the 5th dimension. There are places in each world, soft places, that allow you to step greater distances along The Long Nauvis. Unfortunately stepping does not come without consequence. Each step will physically hurt you and for some strange, unknown reason, no iron, or anything made from iron, can step across with you.
This mod is directly inspired by Terry Pratchet's and Steven Baxter's book 'The Long Earth'