Choose parts, or print color parts

A multi-part model starts on just the part you painted, because that is usually the one you are making. Switch to the whole model, or tick the ones you want. The part carrying your artwork always goes in, since a file without it has no artwork to print. Parts you leave out are dropped from the file entirely, and show as ghosts on the 3D preview. Click any part on that preview to add or remove it, whichever option is selected. The list follows your clicks.

Normally the colors are painted onto the face. The print is one solid piece, and the color rides along as paint data your slicer reads. Turn this on and each color becomes its own part instead, as deep as you choose. The color is then in the shape rather than on it, and any slicer prints it in color even if it ignores paint data.

How deep the color runs is Color depth in Settings → Printer, 0.6 mm out of the box. You can change it for a single download on the download panel. That depth applies whether the box is on or off. What the box changes is how the depth is carried, as parts of their own rather than as paint your slicer carries down.

The file holds one part per color. If you move or rotate it in your slicer, select all of the parts first, so they stay aligned with each other.