diff --git a/app/DD_PM_WINDREAM/ClassIndexListConverter.vb b/app/DD_PM_WINDREAM/ClassIndexListConverter.vb
index 1a73736..1c1c800 100644
--- a/app/DD_PM_WINDREAM/ClassIndexListConverter.vb
+++ b/app/DD_PM_WINDREAM/ClassIndexListConverter.vb
@@ -9,7 +9,14 @@ Public Class IndexListConverter
     End Function
 
     Public Overrides Function GetStandardValues(context As ITypeDescriptorContext) As StandardValuesCollection
-        Dim indexList = DirectCast(context.Instance, FinalIndexProperties).Indicies
+        Dim indexList = New List(Of String)
+
+        If TypeOf (context.Instance) Is FinalIndexProperties Then
+            indexList = DirectCast(context.Instance, FinalIndexProperties).Indicies
+        ElseIf TypeOf (context.Instance) Is InputProperties Then
+            indexList = DirectCast(context.Instance, InputProperties).Indicies
+        End If
+
         Dim values As New StandardValuesCollection(indexList)
         Return values
     End Function