Including a Component via the Block Library

In the Tree Pane, go to the Outline tab.
In the Library palette, use the combo box to select the category that contains the desired item.
In the item list, select the item you want to add to the component.
Drag the item to the Outline tab or to the drawing area.
The item is included in the edited component and, if you dragged it there, in the drawing area. The properties editor for the included component opens.
Adjust the properties according to your needs and click OK.
If you are working in the block diagram editor for SWCs, connect the pins of the component in the same way as the pins of other diagram items.