Form open two times on PROJECTCHANGED Event

Hi,  i setted up a vbs script to run on Dxdesigner startup. The vbs script open a form (Myform) on ProjectChanged event. When i click on recent project on Dxesigner Welcome page Myform is opened two times.

Why??

Dim dxdApp

Set dxdApp = Application

'Scripting.AddTypeLibrary("ViewDraw.Application")

Scripting.AttachEvents Application, "App"

Scripting.DontExit = True

Sub App_ProjectChanged(prjData)

    Dim fileName

    Dim cmdMgr

    Set cmdMgr = Application.CommandsManager

    Call cmdMgr.ExecuteCommand("form " +fileName)

End Sub