Saving Custom Elements

Hi.I am customizing the specific example of
When i tried to saved the example appearing on the canvas/Scree.The custom elements were not present in the xml code.So kindly let me know how i can save custom-elements in As this is very urgent


This seems to be a duplicate of this topic, right? I think you can find help there. Please try to use the search function before opening new topics (especially when there is a topic quite actual as this one)