“Mrgb Palette” allows you to assign combinations of materials and colors to convenient “palette” buttons which allow you to switch back and forth between different colors and materials with ease.
Similarly when you use a custom material in ZBrush, then close and reload your project, your custom material will have to be re-loaded otherwise it will be using a material index of the swatch that is in that index by default. This is just a limitation of ZBrush. All you have to do to alleviate this, is load the script and press initialize and the proper materials will be re-loaded from your last use of the script.
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