Trouble with Dual Extruders on Taz 5 in Simplify3D

Posted this on the S3D forum but they have the silly first posts are hidden "feature".

Got my Flexi-Dualie yesterday and loaded it up with orange and white ABS.

I went through the set up by Lulz using slicr and pronterface and measuring the squares' centering. They are centerd to within .01mm (closest I can measure with digital calipers). Insane method if you ask me. So, I presumed I would be good to go in S3D.

Not so much.
http://cdn.ipernity.com/200/31/76/37...b7b84d.800.jpg

I put this in the start Gcode for both orange and white processes..

Code:

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G28 ; home all axes
M218 T1 X0.685 Y-51.705 ; Offset for Second Extruder Head

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Those numbers are directly copy pasted from slicr's Extruder 2 panel.

At first, I thought it might be because I had it in two processes it was doubling. That can't be as the offset is clearly not 51+mm in the X. The maximum distance appears to be at about 11'oclock so its not 45deg off nor uniformly off in both X and Y.

So, whats wrong and what did I do incorrectly? And, more importantly, how do I fix this to get it to line up? I guess I could make a square model that has a few layers of each color on top of each other (like the cone) but that seems wasteful of filament.