For developers: Override the ResourceAssemblyInfo property
 The ContentViewDesignerBase class uses a predefined template for its UI. It is located in the Telerik.Sitefinity.Resources assembly. The ContentViewDesignerBase uses the ResourceAssemblyInfo property to locate its resources. You must override this property to return a type form the Telerik.Sitefinity.Resources assembly. 
 To do this, perform the following:
  - Add a reference to the Telerik.Sitefinity.Resources assembly.
 You can find the assembly in folder C:\Program Files (x86)\Telerik\Sitefinity CMS 4.0\Libraries.  - Override the ResourceAssemblyInfo property to return the type of the Reference class, using the following code sample:
   protected override Type ResourcesAssemblyInfo
 {
     get
     {
         return typeof(Telerik.Sitefinity.Resources.Reference);
     }
 }