Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Mode
MDATA_SDSWEIGHT_MODE
Parameter: Strength
MDATA_SDSWEIGHT_STRENGTH
Parameter: Set
MDATA_SDSWEIGTH_SETSTRENGTH
Parameter: Interactive Minimum
MDATA_SDSWEIGHT_INTERACTIVEMIN
Parameter: Interactive Maximum
MDATA_SDSWEIGHT_INTERACTIVEMAX