Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Points
ID_CA_CLUSTER_OBJECT_LINKParameter: Target
ID_CA_CLUSTER_OBJECT_TARGETParameter: Set
ID_CA_CLUSTER_OBJECT_TARGET_ADDParameter: Strength
ID_CA_CLUSTER_OBJECT_STRENGTHParameter: Transform
ID_CA_CLUSTER_OBJECT_TRANSFORMParameter: Matrix
ID_CA_CLUSTER_OBJECT_MATRIXParameter: Axis
ID_CA_CLUSTER_OBJECT_ALIGN_AXISParameter: Falloff
ID_CA_CLUSTER_FALLOFF_MODEParameter: Type
ID_CA_CLUSTER_FALLOFFParameter: Radius
ID_CA_CLUSTER_FALLOFF_RADIUSParameter: Width
ID_CA_CLUSTER_WIDTHParameter: Hardness
ID_CA_CLUSTER_HARDNESSParameter: Curve
ID_CA_CLUSTER_FALLOFF_CURVEParameter: Maintain
ID_CA_CLUSTER_OBJECT_MAINTAIN_OFFSETParameter: P
ID_CA_CLUSTER_OBJECT_MAINTAIN_P_OFFSETParameter: R
ID_CA_CLUSTER_OBJECT_MAINTAIN_R_OFFSETParameter: S
ID_CA_CLUSTER_OBJECT_MAINTAIN_S_OFFSETParameter: P
ID_CA_CLUSTER_OBJECT_P_WEIGHTParameter: Map
ID_CA_CLUSTER_OBJECT_P_WEIGHT_MAPParameter: R
ID_CA_CLUSTER_OBJECT_R_WEIGHTParameter: Map
ID_CA_CLUSTER_OBJECT_R_WEIGHT_MAPParameter: S
ID_CA_CLUSTER_OBJECT_S_WEIGHTParameter: Map
ID_CA_CLUSTER_OBJECT_S_WEIGHT_MAPParameter: Effectors
ID_CA_CLUSTER_EFFECTOR