In Solution Explorer, under the AdvancedHMIControls project, right click ChartBySample.vb and select View Code
Go to line 233 and look for this code:
'* V3.99e - added time option
If MyBase.Series(index).XValueType = DataVisualization.Charting.ChartValueType.Time Then
Change the .Time to the type that you selected for the XValueType