Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Stop at Boundary Edges
MDATA_LOOP_SEL_STOP_AT_BOUNDSParameter: Select Boundary Loop
MDATA_LOOP_SEL_SELECT_BOUNDSParameter: Greedy Search
MDATA_LOOP_SEL_GREEDY_SEARCH