AxisRenderer is not aware of the location of Plot components that display graphics on same Axis, and will not match series coordinates correctly if the plots are not aligned with the AxisRenderer. You can ensure axis renderer and plots are aligned by placing them in same StackPanel, or in same row or column of a GridPanel.

System.Object
    MindFusion.Charting.Components.Component
        MindFusion.Charting.AxisRenderer
            MindFusion.Charting.RadarAxisOptions
            MindFusion.Charting.XAxisRenderer
            MindFusion.Charting.YAxisRenderer

AxisRenderer Members
MindFusion.Charting Namespace