Particle flow provides two commands for resetting Particle View and for cleaning up Particle Flow. These are available from Customize User Interface and MAXScript.
Moves the Particle View dialog to its default position. If a scene is opened and saved on different computer systems with different resolutions, you might find that the Particle View dialog has been placed off-screen with regard to your system. Reset Particle View option restores the default position and makes the dialog visible on any computer system.
Removes items that can slow down rendering and editing. When a you create or modify a Particle Flow system, invisible items are sometimes created in the flow network. If you change the PF system during playback, these items allow the PF system to display changes immediately in viewports. However, the items might slow down rendering or editing. Clean Up Particle Flow deletes the invisible items safely, improving render speed and interactivity during Particle View editing.
It is recommended that you use this option after editing Particle View wiring and before rendering or saving the scene.