The layers tab allows you to create and manage drawing layers.

Add and delete layers to the drawing using the "+" and "-" buttons.

Rearrange the layers by dragging. The small arrow to the right of the "Layer" column points to the top layer. This arrow also indicates the order in which the layers will be drawn. Clicking on the header of the table changes the direction of display of the list of layers (but not the drawing order).

Show and hide the layers with the checkbox using the (☼) column of the list. Hidden layers do not appear in reports.

Objects in the current layer can always be selected. The checkbox in the far right column (☞) makes the objects in that layer selectable even when it is not the current layer.

The current layer, indicated by the highlighted radio button, is the one selected for editing. New objects will be added to this layer.

Light symbols only interact with positions contained in the same layer or any selectable layers. It is best to always draw light symbols in the same layer as the position. As stated, a symbol can be associated with a position in a different, currently selectable layer. But, if that setting changes, the light will no longer be able to find the position.