The File Path Editor only recognizes registered nodes and attributes. Reference, file, image plane, and audio nodes are registered by default. Any other node that has an attribute with the usedAsFilename flag can be registered. The usedAsFilename flag can be added with the addAttr command.
This requirement lets you control what is displayed in the File Path Editor, and allows for the support of custom node types from plug-ins and scripts.
To register an element with the File Path Editor
The element is saved automatically to the filePathEditorRegistryPrefs.mel file in your preferences folder. See Preferences.
To deregister an element with the File Path Editor
For example, to deregister an audio node, enter the command filePathEditor -deregisterType "audio.filename";
The element is automatically removed from the filePathEditorRegistryPref.mel file in your preferences folder and all parts of the File Path Editor.