The plugin below draws the following path diagram.

Imports Microsoft.VisualBasic
Imports Amos
<System.ComponentModel.Composition.Export(GetType(IPlugin))>
Public Class CustomCode
Implements IPlugin
Public Function Mainsub() As Integer Implements IPlugin.Mainsub
Dim E As PDElement
Pd.FileNew(Pd.PDSaveChangesEnum.pdPromptToSaveChanges)
E = Pd.DiagramDrawObserved(3, 3, 2, 1)
Pd.DiagramDrawUniqueVariable(E)
Pd.Refresh()
Pd.EditFitToPage()
End Function
Public Function Name() As String Implements IPlugin.Name
End Function
Public Function Description() As String Implements IPlugin.Description
End Function
End Class