Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See page_maxonapi_getting_started_foundations_cinema_parameters.
Parameter: Initialize
ID_CA_SMOOTHING_DEFORMER_OBJECT_INITIAL
Parameter: Restore
ID_CA_SMOOTHING_DEFORMER_OBJECT_RESTORE
Parameter: Strength
ID_CA_SMOOTHING_DEFORMER_OBJECT_STRENGTH
Parameter: Type
ID_CA_SMOOTHING_DEFORMER_OBJECT_TYPE
Parameter: Iterations
ID_CA_SMOOTHING_DEFORMER_OBJECT_ITERATIONS
Parameter: Stiffness
ID_CA_SMOOTHING_DEFORMER_OBJECT_STIFFNESS
Parameter: Keep Displacements
ID_CA_SMOOTHING_DEFORMER_OBJECT_DELTA_LOCK
Parameter: Stiffness Map
ID_CA_SMOOTHING_DEFORMER_OBJECT_STIFF_MAP