Robo 3D R1+ Dual Extrusion One Hotend

This is my first attempt at dual extrusion on my Robo3D R1+. I took the wade extruder file from http://www.thingiverse.com/thing:729956, and modified it to fit the R1+ quick release hotend, as well as to include a separate filament path with a y-junction inside the part. I'm hoping to make a similar setup to the prometheus dual extrusion system (https://www.kickstarter.com/projects/811909269/the-prometheus-system-intuitive-multi-filament-3d).

The whole assembly is only a half inch taller tha