Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Spline Subdivision Factor
COLLADA_IMPORT_SPLINE_SUBDIVISION_FACTORParameter: Import 2D Geometry
COLLADA_IMPORT_2D_GEOMETRYParameter: Import Animation
COLLADA_IMPORT_ANIMATIONParameter: Fix Transparency for Incompatible Files
COLLADA_IMPORT_FORCE_TRANSPARENCY_OPAQUE_MODE_TO_RGB_ZERO