This explanation is a bit unclear to me. It seems to conflate stroke color and fill color for a single object and doesn’t make the distinction between a non-fill which might appear white on the screen, but in fact has no color, which is different from an object filled with the color white, RGB 555,555,555.
An object that has both a fill and a stroke defined will default to a cut/score. You can however change it to an engrave but it won’t do both during a print. To cut out and engraved shape, you have to have a separate color defined, either fill or stroke, to do it in one print.
And you can make a shape that has a defined fill color with no defined stroke color which normally would default to engrave to make that operation into a cut. But always either or.
The depth of the engrave depends on the settings of the operation for that color, not really having anything to do with the color itself. The only variable that color controls is the order of an operation as it is pulled into the GFUI. First Black and last white, and counting from hex 000000 to ffffff.
I believe are saying that you have figured out how to make the strokes and the filled shapes of objects with different colors so that they become separate operations in the GFUI and you can adjust the settings of each precisely.
Just want to make sure I understand you and say I’m glad you figured it out. It is something that requires some knowledge of how vector design programs work and what makes up an SVG. That is some significant computer literacy you are achieving.