LayerMuxer

Image 1 and Image 2 accept images that can contain named layers. Layers may hold render passes or other data, but Z or Vector channels inside an image do not automatically imply a separate layer with that name. Inspect the source in Fusion.

Layer selects only layers from the clip connected to Image 2. Default Layer takes that source’s default layer when one exists; All Layers takes its available layer set; Custom opens a checklist for selecting multiple individual layers. This menu does not filter the first input’s layers.

When a choice other than All Layers is active, Fusion displays a small layer icon on the node. It indicates selective transfer rather than a connection error. Recheck Custom after replacing an EXR or render version because its list comes from the current second source.

Despite its name, the documented Conflicts control selects Default/[Main]: Use Image 1 chooses the first source and Use Image 2 chooses the second. It is not a documented promise to replace every equally named AOV with the selected source. Use distinct layer names and inspect ambiguous names individually.

Changing the layer list may leave the current Viewer image unchanged. Inspect the main image, then view the added layers and their alpha individually. A name appearing in the list does not prove that the layer contains the intended data version.

When saving the multilayer result, check the chosen format and Saver settings, then reload a short test. The image inside the Flow, exported EXR layers and a conventional video file are different delivery stages. Do not assume that all layers are saved automatically.