Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Target
FBXIMPORT_NODESPACE
Parameter: Geometry
FBXIMPORT_GEOMETRY
Parameter: Curves
FBXIMPORT_CURVES
Parameter: Cameras
FBXIMPORT_CAMERAS
Parameter: Lights
FBXIMPORT_LIGHTS
Parameter: Instances
FBXIMPORT_INSTANCES
Parameter: Markers
FBXIMPORT_MARKERS
Parameter: Subdivision Surface
FBXIMPORT_SDS
Parameter: Deformation
FBXIMPORT_ACTIVATE_JOINTS
Parameter: Normals
FBXIMPORT_NORMALS
Parameter: Vertex Colors
FBXIMPORT_COLORS
Parameter: Grayscale to Vertex Maps
FBXIMPORT_COLORS_AS_VERTEX_MAPS
Parameter: Up Axis
FBXIMPORT_UP_AXIS
Parameter: Flip Z Axis
FBXIMPORT_FLIP_Z_AXIS
Parameter: Tracks
FBXIMPORT_TRACKS
Parameter: Clean Tracks
FBXIMPORT_CLEAN_TRACKS
Parameter: Vertex Cache to PLA
FBXIMPORT_VERTEXCACHE_TO_PLA
Parameter: Poses
FBXIMPORT_SHAPES
Parameter: Material
FBXIMPORT_MATERIALMODE
Parameter: Substances
FBXIMPORT_SUBSTANCES
Parameter: Single Material Selection Sets
FBXIMPORT_SINGLE_MAT_SELECTIONTAGS