I wish to use Region to create struts and springs to assist in laying out child nodes in HBoxes and VBoxes.
This approach was described in the JavaOne 2011 presentation Interface Layout with JavaFX 2.0 (Amy Fowler).
The left-side list of Containers in SB does not include Region, and I would prefer not to debase an existing container or control to achieve the result.
Please add Region and perhaps Pane to the list of available containers.