ColorToSolidColorBrushConverter: implemented ConvertBack method. Although not used in the toolkit, a user has requested this functionaltiy and provided a patch.

ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/Core/Converters/ColorToSolidColorBrushConverter.cs

@@ -8,6 +8,16 @@ namespace Microsoft.Windows.Controls.Core.Converters
     {
         #region IValueConverter Members
 
+        /// <summary>
+        /// Converts a Color to a SolidColorBrush.
+        /// </summary>
+        /// <param name="value">The Color produced by the binding source.</param>
+        /// <param name="targetType">The type of the binding target property.</param>
+        /// <param name="parameter">The converter parameter to use.</param>
+        /// <param name="culture">The culture to use in the converter.</param>
+        /// <returns>
+        /// A converted SolidColorBrush. If the method returns null, the valid null value is used.
+        /// </returns>
         public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
         {
             if (value != null)
@@ -16,9 +26,24 @@ namespace Microsoft.Windows.Controls.Core.Converters
             return value;
         }
 
+
+        /// <summary>
+        /// Converts a SolidColorBrush to a Color.
+        /// </summary>
+        /// <remarks>Currently not used in toolkit, but provided for developer use in their own projects</remarks>
+        /// <param name="value">The SolidColorBrush that is produced by the binding target.</param>
+        /// <param name="targetType">The type to convert to.</param>
+        /// <param name="parameter">The converter parameter to use.</param>
+        /// <param name="culture">The culture to use in the converter.</param>
+        /// <returns>
+        /// A converted value. If the method returns null, the valid null value is used.
+        /// </returns>
         public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
         {
-            throw new NotImplementedException();
+            if (value != null)
+				return ((SolidColorBrush)value).Color;
+
+            return value;
         }
 
         #endregion