Sample for Developing Frames,Tray Supports,HVAC Supports in OPSE

hello

   There is a support development Manual present in the installation folder of OPSE, but the methods of developing support frameworks, Tray Supports and HVAC Supports are not mentioned in document.Placement methods for such supports start with BESM script mnuCantilever, BESM script mnuTraySupport, BESM script mnuHVACSupport，However, all the references in the document are to use the command besm script mnuPlacement to place a bracket.When I developed Cantilever with the way described in the help document, I could not creat a compoment which is allows dynamic stretch input during placement,and after add connectors using method BasicShapes.AddConnector in my geometry , it could only place at the coordinate origin (0, 0, 0).
   Where can I find some examples of Python scripts for developing such bracket?

Thanks