Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Tension
MDATA_SETEDGEFLOW_TENSIONParameter: Maximum Angle
MDATA_SETEDGEFLOW_ANGLELIMITParameter: Equal Spacing
MDATA_SETEDGEFLOW_EQUALSPACINGParameter: Linear
MDATA_SETEDGEFLOW_LINEARParameter: Fallback Mode
MDATA_SETEDGEFLOW_FALLBACKMODE