You can quickly build and edit multi-layer compositions using the Layer Editor. As in the Schematic view, you can use the Reaction drop gate to quickly build your initial composition, and can drop tools directly onto layers.
The Layer Editor's context menu also lets you access the Pick List, select the layer's component nodes, such as materials, and other tool nodes associated with the selected layer. When you select a Reaction node or tool, the appropriate panel in the Tool UI is displayed, so you can modify properties interactively. For more information, see Creating Sources and Layers.
To add tools to a layer in your composition:
The tool is added before the source input for the layer, and its Tool UI is displayed.