Instead of placing components from top to bottom, add a TabSheet to the sample view with 2 tabs: "Declaratively added component" and "Programmatically added component".
Improve the description:
Explain what custom component is for: to reuse UI parts in different views, etc.
Explain what custom component can do: contain other components, load data, connect to data containers of the host view, etc.
Explain the example: "In this example, we explain how to create and use a custom component for editing addresses. The component consists of ... edit fields, it loads lists of countries and cities, it saves values to ..."
Fixed, @KremnevDmitry please take a look