There are many discussions regarding 3D engraves which might help you: Search results for '3D engrave' - Glowforge Owners Forum
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It’s called a “depth map.” It’s grayscale with the value of the gray indicating the depth to carve at that point. 
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Try mineral oil (baby oil) works like a charm for acrylic removing paint or the white powder after cutting and engraving it clears it all right up