SeeMeCNC Rostock MAX v2 Assembly Manual page 308

Grid hides or displays the virtual print surface.
Moves will show you the path the print head takes when it's not printing,
as shown by the light green lines in the image below.
Fig. 28-7: Travel moves.
Retractions show the points in the print where the extruder is going to retract filament from the
hot end. This is done either during a non-printing move, or when changing extruders.
The red and blue points in the image to the
right show where the retractions are happening.
Red shows the retract operation while the
blue color shows the resume/extrude.
Speeds will color the layers based on how fast the layer is printed.
Rostock MAX v2 Assembly Guide
Fig 28-9: Layer speed.
Fig. 28-8: Retracts.
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