Where to instantiate wrapper class?

I'm using VC# 2010 Express to create a multi-form application, for dot Net 4.
I created several DLLs in order to separate functional implementations - eg file IO, data manipulation, etc. Both the form classes and the DLL classes have C# interfaces, to make out-calls to the DLLs. I opted to implement all the interfaces and instantiate the DLL's in one wrapper class, IFClass. But now the problem is where to instantiate the IFClass so that a form can access the IFClass members?

I tried instantiating the wrapper class in the main form class, but was refused - I get a message that says it would cause circular references.

So...where do I instantiate IFClass?

I don't really want to make the DLLs static - had hoped to do it all with dynamic code.

Here is some code:

Code:

---

//Mainform.cs
using System;
using System.Windows.Forms;
//Can't reference IFClass here: Cicular reference.
namespace WrapperClassTest1
{
        public partial class Mainform : Form
        {
                public Mainform()
                {        InitializeComponent();        }
//The button on the main form would open Subform1
                private void btnGoSubform1_Click(object sender, EventArgs e)
                {        /*...*/ }
        }
}
--------
//Subform1.cs
using System;
using System.Windows.Forms;
namespace WrapperClassTest1
{
        public interface ISubform1
        {        void OutfromSubform1(); }
        public partial class Subform1 : Form
        {
                public Subform1()
                {        InitializeComponent();        }
        }
}
----------
//ClassA.cs
namespace nsClassA
{
        public interface IClassA
        {        void OutfromClassA();        }
        public class ClassA
        {        }
}
----------------
//IFClass.cs
using System;
using WrapperClassTest1;
using nsClassA;
namespace nsIFClass
{
        public class IFClass: IClassA, ISubform1
        {
                //ClassA CA = new ClassA();
                public void OutfromClassA()
                { }
                public void OutfromSubform1()
                { }
        }
}

---