Colour Mixer Issues

[Smurf]

I have a recently purchased A10M which works fine. I now want to do a simple and sudden colour change half way up a print. After downloading the Win+Beta version of "Colour Mixer", I've followed the "speechless" Geeetech videos, and slicing appears to work, but inspection of the resulting g-code shows no extruder/filament swap at any layer.
I have trawled this forum, the Geeetech site, YouTube videos without any success in finding how to do this. Maybe it's impossible with this type of printer. If that's the case I will be ditching it. I already have an i3 Pro, where I manually change the filament mid-print. I use Repetier Host and Slic3r but do not want to change to Cura or other slicing software. If anyone knows how to do such a relatively simple task, I'm all ears ?