Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: MATERIAL_PAGE_PROPERTIES
MATERIAL_PAGE_PROPERTIESParameter: Render Objects
PSIMF_RENDOBJParameter: Render Hidden Objects
PSIMF_RENDHOBJParameter: Render Mode
PSIMF_RENDMODEParameter: World Step Size
PSIMF_STEPParameter: Ray Trans. Limit
PSIMF_LIMITParameter: ShadowMap Step Size
PSIMF_MAPSTEPParameter: ShadowMap Trans. Limit
PSIMF_MAPLIMITParameter: Raytraced Step Size
PSIMF_SHADSTEPParameter: Raytraced Trans. Limit
PSIMF_SHADLIMITParameter: RayTrans. Correction
PSIMF_RTCORRECTParameter: Volume Light
PSIMF_VOLFILTER