Chart Series not Visible on Initial View

Thank you, Valerie. The sample code you provided worked fine on my machine ( I used the version utility to roll the IGreferences back to 14.1). I think this must be related to binding or my VM properties.

Here is the XAML for the series in question:

<ig:RadialLineSeries Title="Current" x:Name="seriesCurrent" MouseLeftButtonDown="rt_MouseMove"
                                                     ItemsSource="{Binding Meas_HI_Data, Mode=TwoWay}" 
                                            ClipSeriesToBounds="True"
                                            AngleAxis="{Binding ElementName=angleAxis}" 
                                            ValueAxis="{Binding ElementName=radiusAxis}" 
                                            ValueMemberPath="Value"
                                            Visibility="{Binding Meas_HI_Data.Visible, 
                                                         Converter={StaticResource VisibilityConverter}}"                   
                                            Brush="Brown"                                        
                                            MarkerType="Circle" MarkerBrush="Brown"                                                 
                                            >
                                    <ig:RadialLineSeries.ToolTip>
                                        <Border BorderBrush="Black" BorderThickness="1" Background="Azure">
                                            <StackPanel Orientation="Vertical" Margin="3">
                                                <TextBlock Text="{Binding Item.Label}"/>
                                            </StackPanel>
                                        </Border>
                                    </ig:RadialLineSeries.ToolTip>
                                </ig:RadialLineSeries>

And the property it is bound to:

  private CategoryDataCollection m_Meas_HI_Data;
        public CategoryDataCollection Meas_HI_Data
        {
            get
            {
                return m_Meas_HI_Data;
            }
            set
            {
                if (m_Meas_HI_Data == value)
                {
                    return;
                }
                m_Meas_HI_Data = value;
                NotifyPropertyChanged("Meas_HI_Data");
            }
 
        }

CategoryDataCollection was copied from an Infragistics sample with one added property (Visible) which I use to control the display of individual series. I also changed to INotifyPropertyChanged for the CategoryDataPoint type to make it compatible with the rest of my VM. Starting to wonder if that was a good idea, or if I didn't implement the observable interface right.

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel; 
using System.ComponentModel;
using System.Linq;
 
{
    public class CategoryDataCollection : ObservableCollection<CategoryDataPoint>
    {
        public CategoryDataCollection()
        {
            _title = "";
        }
        private string _title;
        public string Title
        {
            get { return _title; }
            set
            {
                if (_title.Equals(value)) return;
                _title = value;
                OnPropertyChanged(new PropertyChangedEventArgs("Title"));
            }
        }
        private bool _visible;
        public bool Visible
        {
            get { return _visible; }
            set 
            { 
                if (_visible == value) return; 
                _visible = value; 
                OnPropertyChanged(new PropertyChangedEventArgs("Visible")); 
            }
        }
    }
 
    public class CategoryDataPoint : INotifyPropertyChanged
    {
        public CategoryDataPoint() { }
        public CategoryDataPoint(double value, string cat, string label)
        {
            this.Value = value;
            this.Category = cat;
            this.Label = label;
        }
        public CategoryDataPoint(CategoryDataPoint dataPoint)
        {
            this.Index = dataPoint.Index;
            this.Category = dataPoint.Category;
            this.Value = dataPoint.Value;
            this.Date = dataPoint.Date;
            this.High = dataPoint.High;
            this.Low = dataPoint.Low;
        }
        public double Change
        {
            get { return High - Low; }
        }
        public double ChangePerCent
        {
            get { return (Change / High) * 100; }
        }
        private double _index;
        public double Index
        {
            get { return _index; }
            set { if (_index == value) return; _index = value; NotifyPropertyChanged("Index"); }
        }
        private double _value;
        public double Value
        {
            get { return _value; }
            set { if (_value == value) return; _value = value; NotifyPropertyChanged("Value"); }
        }
        private double _high;
        public double High
        {
            get { return _high; }
            set { if (_high == value) return; _high = value; NotifyPropertyChanged("High"); }
        }
        private double _low;
        public double Low
        {
            get { return _low; }
            set { if (_low == value) return; _low = value; NotifyPropertyChanged("Low"); }
        }
        private string _category;
        public string Category
        {
            get { return _category; }
            set { if (_category == value) return; _category = value; NotifyPropertyChanged("Category"); }
        }
 
        private string _label;
        public string Label
        {
            get { return _label; }
            set { if (_label == value) return; _label = value; NotifyPropertyChanged("Label"); }
        }
 
        private DateTime _date;
        public DateTime Date
        {
            get { return _date; }
            set { if (_date == value) return; _date = value; NotifyPropertyChanged("Date"); }
        }
        public new string ToString()
        {
            return String.Format("Category {0}, Value {1}", Category, Value);
        }
 
        #region INotifyPropertyChanged Implementation
        public event PropertyChangedEventHandler PropertyChanged;
        private void NotifyPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
        #endregion
    }
 
    //public abstract class ObservableModel : INotifyPropertyChanged
    //{
    //    #region INotifyPropertyChanged
    //    public event PropertyChangedEventHandler PropertyChanged;
    //    protected void OnPropertyChanged(string propertyName)
    //    {
    //        if (this.PropertyChanged != null)
    //            this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    //    }
 
    //    #endregion
    //}
 
}