Cool, you are on your way! You cannot edit an existing instance of the component to cut as the “cutting” is applied when the component is first placed. So once you have “component window-glue to vert-cut opening” all set you will need to place a new instance of the window to see it cut, all subsequent instances will cut. If you hit a snag check the axes inside the window component, it’s a common mistake. The blue axis needs to be perpendicular to the “glass” or opening you want to cut in order to tell SkUp which face to use, it’s an easy one to overlook and without it you won’t get a cut. You can change the axis inside the component while it’s being edited with the axis tool or you can build a new window “flat” on the ground before you make it a component then rotate it 90 after to end up with a component that has the blue axis pointing away from the face. Different skinnings of the same cat.
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