creo7 config.pro option documentation for: DXF_OUT_SCALE_VIEWS 
dxf_out_scale_views
yes
, no
*
Specifies whether to scale drawing views when exporting to the DXF or DWG file format. This configuration option is available as the Scale drawing views when exporting to DXF or DWG format
2D data exchange setting in the Creo Parametric Options
dialog box.
yes
- Rescales the entire drawing such that the scale becomes 1:1 for the view named main_view
.
no
- Exports without rescaling the drawing.