NC DATA output .dxf Error


I am experiencing an error with the produced .dxf files using the NC DATA tool.

It seems that all of the output drawings are rounded upto the nearest mm in dimension.

For example in the attached .dxf the slot dimensions in the model are 24.49x8.0mm / Output is 24x8.0mm.

Overall length of part in the model is 1167.57, output is 1168

I have attached a sample output .dxf and snapshot of dialog boxes. 

Any ideas how to address this issue?

I am using AutoCAD V8i (SELECTseries 6) - Version