Code example:

procedure TMainFrm.Button1Click(Sender: TObject); 
var 
  SrcShape,DestShape:TMyShape;   
begin 
  //... 
  if MyCAD1.GetShapeByName('LinkLineShape')=nil then 
    begin 
    if MyCAD1.CreateLink('LinkLineShape',SrcShape,0,DestShape,1)>-1 then  
       ShowMessage('Created Success!') 
      else 
       ShowMEssage('Created failed!'); 
    end 
  else 
    ShowMessage('LinkLine Shape has been created!'); 
end;