Hi,
You can modify the PropertyGrid in the CollectionControl's Template. To do so, just add your "PropertyGrid.EditorDefinitions" to the PropertyGrid in the CollectionControl's Template. You will find it in :
-Xceed.Wpf.Toolkit/CollectionControl/Themes/Aero2.NormalColors.xaml (for Windows8)
-Xceed.Wpf.Toolkit/CollectionControl/Themes/Generic.xaml (for others windows)
You can modify the PropertyGrid in the CollectionControl's Template. To do so, just add your "PropertyGrid.EditorDefinitions" to the PropertyGrid in the CollectionControl's Template. You will find it in :
-Xceed.Wpf.Toolkit/CollectionControl/Themes/Aero2.NormalColors.xaml (for Windows8)
-Xceed.Wpf.Toolkit/CollectionControl/Themes/Generic.xaml (for others windows)