Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See page_maxonapi_getting_started_foundations_cinema_parameters.
Parameter: Offset
MDATA_EDGECUT_OFFSET
Parameter: Scale
MDATA_EDGECUT_SCALE
Parameter: Subdivision
MDATA_EDGECUT_SUBDIV
Parameter: Create N-gons
MDATA_EDGECUT_CREATENGONS
Parameter: N-gons
MDATA_EDGECUT_NGONMODE