control.Region(n).LineSeries(n).SeriesStyle
Type:Long (LineSeriesStyle constant)
Purpose:Sets the style of a Line series
Default:Line flat (RMC_LINE_FLAT)
Accessible:Runtime
Remarks:

Between the properties SeriesStyle and SeriesType exists an obvious interdependency: only the Line...Types can have Line...Styles, and only Area...Types can have Area...Styles.
There is one more restriction: if the grid's data axes have the alignment Top or Bottom, only the 2D SeriesStyles are available.

Example:RMChartX1.AddRegion
RMChartX1.Region(1).AddLineSeries
RMChartX1.Region(1).LineSeries(1).SeriesStyle = RMC_LINE_3D