Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See page_maxonapi_getting_started_foundations_cinema_parameters.
Parameter: Texture
XNORM_SHADERLINK
Parameter: Strength
XNORM_STRENGTH
Parameter: Filter
XNORM_FILTER
Parameter: Invert
XNORM_INVERT
Parameter: Delta
XNORM_DELTA
Parameter: Clamp UV
XNORM_CLAMP_UV