Simplified 3d will not run extruder I downloaded simplified 3d to use with Mach 3 everything seems to work properly except for the extruder which will not communicate with the new software. Not moving filament that is my only problem what is going on?
To use Mach3 to send printing you need to define the extruder as A instead E, since Mach3 only drives X,Y,Z,A and B motors. you can see an explanation here on is possible to send printing with mach3? Question. 

I haven't tried to see if is possible to change this letters directly on 3D simplify, because i'm using ramps 1.4 instead the CNC driver control. But there is an ADDON to slice your gcode with Mach3 called gnexlab, try to find it on google search. I've downloded few years ago.

Added Link 
gnexlab Addon