Can you tell me what problem you are having? Are these methods not being fired? Have you made sure that you have set your chart's delegate?
To enable the type of selection you want you also need to make sure that you have set each series' selectionMode property. You can set this to SChartSelectionSeries if you want the toggledSelectionForSeries method to called, or to SChartSelectionPoint if you want the SChartSelectionForPoint method to be called.
Let me know how you get on!