Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Mode
MDATA_LIGHTPLACER_MODE
Parameter: Selection Method
MDATA_LIGHTPLACER_SELMODE
Parameter: Modify Lights Only
MDATA_LIGHTPLACER_LIGHTONLY
Parameter: Highlighting
MDATA_LIGHTPLACER_HIGHLIGHTING
Parameter: Quick Interaction
MDATA_LIGHTPLACER_QUICK
Parameter: Pivot
MDATA_LIGHTPLACER_PIVOT
Parameter: Place Pivot
MDATA_LIGHTPLACER_PLACEPIVOT
Parameter: Add Light
MDATA_LIGHTPLACER_ADDLIGHT