Подключение DLL к VBA

Формулировка задачи:

Добрый день!
Создаю в VB .NET библиотеку DLL.

Public Class erunda
    Public Overloads Shared Sub AddNum(ByVal a() As Double, ByVal d() As Double, ByRef c As Double)
        Dim ff As Double
        ddd_q(d, ff)
        c = aaa_q(a) + ff
    End Sub
    Public Overloads Shared Function aaa_q(ByVal a() As Double) As Double
        Dim i As Integer
        aaa_q = 0
        For i = 1 To a(0)
            aaa_q = aaa_q + a(i)
        Next i
        Return aaa_q
    End Function
    Public Overloads Shared Sub ddd_q(ByVal d() As Double, ByRef ff As Double)
        Dim i As Integer
        ff = 0
        For i = 1 To d(0)
            ff = ff + d(i)
        Next i
    End Sub
End Class

Проверяю на работоспособность полученную библиотеку в другом проекте на VB .NET. Всё исправно.
Далее хочу ею воспользоваться из макроса VBA.
Регистрирую библиотеку в системе. Пишу к примеру такой код в макросе:

Public Declare PtrSafe Sub AddNum Lib "ClassLibrary1" (ByVal a As Double, ByVal d As Double, ByRef c As Double)

Sub test()
   Dim a() As Double: ReDim a(2)
   Dim d() As Double: ReDim d(2)
   Dim c As Double
   a(0) = 2: a(0) = 3: a(0) = 4
   d(0) = 2: d(0) = 5: d(0) = 6
   'Dim my_class As New erunda
   Call AddNum(a, d, c)
End Sub

ошибка естесна...
Как я только не пробовал писать. Перебрал практически всё ,что можно было нагуглить.
Результат ошибка "object required", "библиотека не найдена", ... вовщем ппц.
Помогите разобраться.
Да кстати, система у меня win 7 профешнл 64bit=)

Решение задачи: «Подключение DLL к VBA»

textual
                            Листинг программы 
                        

                            Public Interface iSPL
    Sub AddNum(ByVal a() As Double, ByVal d() As Double, ByRef c As Double)
    Function aaa_q(ByVal a() As Double) As Double
    Sub ddd_q(ByVal d() As Double, ByRef ff As Double)
End Interface

Public Class SPL
    Implements iSPL

    Public Sub AddNum(ByVal a() As Double, ByVal d() As Double, ByRef c As Double) Implements iSPL.AddNum
        Dim ff As Double
        ddd_q(d, ff)
        c = aaa_q(a) + ff
    End Sub
    Public Function aaa_q(ByVal a() As Double) As Double Implements iSPL.aaa_q
        Dim i As Integer
        aaa_q = 0
        For i = 1 To a(0)
            aaa_q = aaa_q + a(i)
        Next i
        Return aaa_q
    End Function
    Public Sub ddd_q(ByVal d() As Double, ByRef ff As Double) Implements iSPL.ddd_q
        Dim i As Integer
        ff = 0
        For i = 1 To d(0)
            ff = ff + d(i)
        Next i
    End Sub
End Class

                        