Two-Motor Multi-Material Printing... How to implement in Firmware?

Hey Guys,

I'm trying to do something that I don't think has been done before. Okay... its an adaptation of MMU.V2. But I don't think it would be very hard... at least for someone with just a little more experience. Pretty much I'm hoping to crowd-source the solution to this problem.

I want to try and create a multi-colour extruder that will print up to 5 (possibly more) different colours, with one nozzle, and two motors(Single Board). This should drastically reduce the cost to implement the solution. This means no extra boards, no extra cables, only one motor, and then some hardware and some printing.

The concept is based off the two images in my poster. Their "Widgets/Parts" can be found on Thingiverse at the following locations:
https://www.thingiverse.com/thing:2867089 - 2-3-4 way Splitter (doesn't have to be this one... it is just representative)
https://www.thingiverse.com/thing:3123202 - Multi-Extruder

I am pretty confident that I can work out the design files to be able to modify the Y Splitter for more (I'm looking for 5) and engineer it so that the Teflon tubes work well (I would also like to see if I can add a filament sensor). As well as verifying the extruder design for what we are trying to achieve. The problem that I have found, at least I expect that it is a problem, the second motor is not extruding, and thus only gets triggered on a change filament command, but then it uses the same extruder once the filament is selected. I figure it wouldn't take much to implement and I can write the pseudo-pseudo code for it (I could even turn this into GCode)... But i don't know how to have this work with a slicer or firmware:

-retract current filament
-set temp and wait
-switch filament
      -move motor 2 appropriately
-purge nozzle and complete wipe tower or wall
-continue printing until next filament change

From the a post in the developers forum (i thought this would mean modifying the code), I have come to realize that a t-code with the right firmware additions in Marlin may be possible. I was advised to post here to see if someone had a solution to help.

Hopefully someone can help