creo4 config.pro option documentation for: SHADE_SURFACE_FEAT 
shade_surface_feat
yes
*
, no
Controls the shading of surface features.
yes
- Shades surfaces.
no
- Does not display surface features with shading.
="ww3_3_6_6_3_33_4_2_2" class="List_1">
no
- Does not convert the IGES group to drawing layers.