The OCE is based on the Necromunda: Outlanders supplement published in 1996. It also includes The Heist scenario and Pit Slave Gang rules from White Dwarf. OCE is not an attempt to overhaul or hugely expand the Necromunda game, instead it should be seen as a fan update to an already solid set of rules.
The main aims are to balance the variety of Outlander gangs using minimal rewrites where possible and to fully incorporate the NCE ruleset. Also to clarify ambiguities, patch up rule holes and make minor tweaks and additions to improve general gameplay.
All changes to the original rules are marked in red.
You can follow development of the project and post suggestions in the NCE discussion thread. Previous discussion here.