In the simple project I have uploaded (a variation of the samples provided by chartFX), you will notice that the legend box circle markers are not all equal. In particular the 2nd and 3rd circles have an uneven height, so it looks like an enlongated circle.
If we use the default marker size everything looks normal. But when setting the marker size in the code behind, that is when the results of the size becomes unexpected. The default marker size is to big for my application so I have a need to make it smaller.
Based on a previous forum post http://community.softwarefx.com/forums/p/10665/25948.aspx I set the legend marker size for 3 series as such:
chart1.LegendBox.ItemAttributes[chart1.Series].MarkerSize =
new Size(6, 6);