Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Stop at Selections
MDATA_RING_SEL_STOP_AT_SELECTIONS
Parameter: Stop at Non-Quads
MDATA_RING_SEL_STOP_AT_NON_QUADS
Parameter: Stop at Poles
MDATA_RING_SEL_STOP_AT_POLES