The really clever part of Colored Layer is that it will temporarily create a new layer called _FINDER_ and assign the object to that layer. This means in very complex models you can easily concentrate on where you need to make changes. As soon as you toggle Color Layer off the object will return to its original layer.
The centre zone, New Material, contains your applied materials and is used to swap materials out based on what you select in the top zone.
The bottom zone, Apply To, is where you get to really fine tune your material replacements. Whether you want to completely swap materials on every element or just target components you can tailor the replacement vey precisely without having to dig through nested elements.
You can watch this video below to see an overview of what Material Maintenance is capable of.
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