Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Shell
GENERATOR_SELECTION_POLYGON_SHELLParameter: GENERATOR_SELECTION_NAME_POLYGON_SHELL
GENERATOR_SELECTION_NAME_POLYGON_SHELLParameter: Start Cap
GENERATOR_SELECTION_POLYGON_CAP_STARTParameter: GENERATOR_SELECTION_NAME_POLYGON_CAP_START
GENERATOR_SELECTION_NAME_POLYGON_CAP_STARTParameter: End Cap
GENERATOR_SELECTION_POLYGON_CAP_ENDParameter: GENERATOR_SELECTION_NAME_POLYGON_CAP_END
GENERATOR_SELECTION_NAME_POLYGON_CAP_ENDParameter: Start Bevel
GENERATOR_SELECTION_POLYGON_BEVEL_STARTParameter: GENERATOR_SELECTION_NAME_POLYGON_BEVEL_START
GENERATOR_SELECTION_NAME_POLYGON_BEVEL_STARTParameter: End Bevel
GENERATOR_SELECTION_POLYGON_BEVEL_ENDParameter: GENERATOR_SELECTION_NAME_POLYGON_BEVEL_END
GENERATOR_SELECTION_NAME_POLYGON_BEVEL_ENDParameter: Start Shell
GENERATOR_SELECTION_EDGE_SHELL_STARTParameter: GENERATOR_SELECTION_NAME_EDGE_SHELL_START
GENERATOR_SELECTION_NAME_EDGE_SHELL_STARTParameter: End Shell
GENERATOR_SELECTION_EDGE_SHELL_ENDParameter: GENERATOR_SELECTION_NAME_EDGE_SHELL_END
GENERATOR_SELECTION_NAME_EDGE_SHELL_ENDParameter: Start Cap
GENERATOR_SELECTION_EDGE_CAP_STARTParameter: GENERATOR_SELECTION_NAME_EDGE_CAP_START
GENERATOR_SELECTION_NAME_EDGE_CAP_STARTParameter: End Cap
GENERATOR_SELECTION_EDGE_CAP_ENDParameter: GENERATOR_SELECTION_NAME_EDGE_CAP_END
GENERATOR_SELECTION_NAME_EDGE_CAP_ENDParameter: Start Step
GENERATOR_SELECTION_EDGE_STEP_STARTParameter: GENERATOR_SELECTION_NAME_EDGE_STEP_START
GENERATOR_SELECTION_NAME_EDGE_STEP_STARTParameter: End Step
GENERATOR_SELECTION_EDGE_STEP_ENDParameter: GENERATOR_SELECTION_NAME_EDGE_STEP_END
GENERATOR_SELECTION_NAME_EDGE_STEP_END