creo4 config.pro option documentation for: INTF_CADDS_IMPORT_MAKE_SOLID 
intf_cadds_import_make_solid
yes
, no
*
Allows you to solidify closed quilts when you import CADDS 5 part and assembly models.
yes
- Imports closed quilts as solids when you import CADDS 5 models.
no
- Does not solidify the closed quilts in the CADDS 5 models when you import the models.