I know its kind of a goofy question but I was wondering if anyone has tried to add a direct Extruder esteps per mm adjustment control to any version of repsnapper or any of the host softwares could be made to do this?

If your firmware supports it, the gcode M92 with an E parameter can do this. The host software only need a way to send gcodes manually then (repsnapper can).

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Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.

Try with Extrusion Multiplier in Printer settings and convert to Gcode

Extrusion Multiplier - 1 denotes actual length
Extrusion Multiplier - 0.5 denotes 50 % of actual length

If your Machine Extrusion is calibrated wrong try with Firmware modification
else for temporary change you can use Extrusion Multiplier