Creating, storing and managing forms dynamically

[PSYCHONAUT]

Hi, I'm making a LAN instant messenger and I'm trying to achieve something similar to how MSN will open a new chatting window when you double click on a friend. My main form has a list of friends, and I want to create a new chat window when they double click on one of those friends. I've created a "template" chat form which I want to generate dynamically, and I've run into some problems I need help with. Lets look at the code I already have.

The sub for double clicking on the friend listbox:

    Private Sub lbFriends_DoubleClick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lbFriends.DoubleClick
       Dim fd() As String = Split(My.Settings.Friends.Item(lbFriends.SelectedIndex), "|"c)
        If lbFriends.SelectedIndex >= 0 Then
            If IsInClientList(fd(0)) = False Then
                Me.Invoke(New del(AddressOf OpenNewChat))
            End If
            'Connection code
        End If
    End Sub

The sub for creating a new chat window, adding it to a list, and showing it:

    Private Sub OpenNewChat()
        Dim NewChatWind As New ClientWind
        CWL.Add(ClientWind)
        CWL.Item(CWL.Count - 1).Show()
    End Sub

And outside of those subs I have this:

    Private Delegate Sub del()
    Dim CWL As New List(Of ClientWind)

The form will only appear once as far as I can tell, and the chat form has events such as button clicks; an error occurs when I try to change something like the text property of a label for example (eg. clicking a button on the chat form changes the text of a label on the chat form will cause an error to occur). The error I actually get is:

Cross-thread operation not valid: Control 'ClientWind' accessed from a thread other than the thread it was created on.

Now, call me a newb if you will, but I really don't know much about threading and all that hocus pocus. Some guidance in the right direction would be great.

EDIT: ClientWind is the chat form.
EDIT: That's weird. It doesn't occur with the actual builds.