Hi,

You can see how to implement drag-and-drop in the "Drag and Drop" and "More Drag and Drop" VB sample projects. This modification of the latter shows how to insert a node, splitting an existing link into two new ones, which happens in the WPF WorkflowDesigner example:

Private Sub FlowChart1_DropInDocVB(ByVal dataObj As FLOWCHARTLibCtl.IVBDataObject, ByVal docX As Long, ByVal docY As Long, ByVal keyState As Long, effect As Long)
    Dim s As String
    Dim b As FLOWCHARTLibCtl.box
    Dim i As Integer

    Dim a As arrow
    Set a = FlowChart1.GetArrowAt(docX, docY)

    If dataObj.GetFormat(vbCFFiles) Then
        'some file are dropped
        For i = 0 To dataObj.FileCount - 1
            s = dataObj.Files(i)
            Set b = FlowChart1.CreateBox(docX + i * 10, docY + i * 50, 250, 40)
            b.Text = s
        Next i
    Else
        'some text is dropped
        s = dataObj.GetData(vbCFText)
        Set b = FlowChart1.CreateBox(docX, docY, 100, 100)
        b.Text = s

        If Not a Is Nothing Then
            SplitLink a, b
        End If
    End If

    effect = vbDropEffectCopy
End Sub

Sub SplitLink(a As arrow, b As box)
    Dim a2 As arrow
    Set a2 = FlowChart1.CreateArrow(b, a.DestinationBox)
    a.Destination = b
End Sub 

If you are interested in the sample layout code, it should be pretty straightforward to port. Our controls' API has evolved a lot since the ActiveX days, but you can still find one-to-one correspondence between the WPF and ActiveX members. E.g. a node.Bounds assignment will become a call to box.SetRect, and link.ControlPoints assignments will become arrow.CtrlPtX/Y assignments.

I hope that helps,
Stoyan