Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Include Children
OUTLINEITAG_INCCHILDREN
Parameter: Allow Lines
OUTLINEITAG_TOONALLOWED
Parameter: Allow Shading
OUTLINEITAG_SHADERALLOWED
Parameter: Render Culling
OUTLINEITAG_MODE
Parameter: Style Tags
OUTLINEITAG_TAGLIST