How to create an object of type Dictionary<string, List<string>>

The dotNET object doesn't currently support creating generics in scripts.

You need to create a helper assembly with a static method that returns the needed dictionary, add this assembly to CLR Bridge, and call this method in your script:

// C#
public static Dictionary<string, string> getGenericStringDictionary()
{
  return new Dictionary<string, string>();
}

// TestComplete/JScript
var oDic = dotNET.your_namespace.yourclass.getGenericStringDictionary();

Update: Actually it's possible to create generics using dotNET and reflection, but it's somewhat lengthy. Here's an example for List<string>, just in case.

In C#, you can create List<string> through reflection like this:

Type typeListOf = typeof(List<>);
Type[] paramTypes = { typeof(string) };
Type typeListOfString = typeListOf.MakeGenericType(paramTypes);
List<string> list = Activator.CreateInstance(typeListOfString) as List<string>;

And the dotNET port of this code is:

// C#: Type typeListOf = typeof(List<>);
var typeListOf = dotNET.System.Type.GetType("System.Collections.Generic.List`1");
// "`1" in "List`1" means that List has 1 type argument: List<string>

// C#: Type[] paramTypes = { typeof(string) };

// Create a Type[] array with 1 element
var paramTypes = dotNET.System.Array.CreateInstance(
                   dotNET.System.Type.GetType("System.Type"), // array item type
                   1); // array length
// Set the array element to the string type object
var stringType = dotNET.System.Type.GetType("System.String"); 
paramTypes.SetValue(stringType, 0 /* array item index */);

// C#: Type typeListOfString = typeListOf.MakeGenericType(paramTypes);
var typeListOfString = typeListOf.MakeGenericType(paramTypes);

// C#: List<string> list = Activator.CreateInstance(listOfString) as List<string>;
var list = dotNET.System.Activator.CreateInstance_3(typeListOfString);

// Specify the list items
list.Add("apples");
list.Add("oranges");