Thanks. I think the problem is that the 2 concentric shapes that you want to fill between are not closed lines. They are 4 separate line segments that are next to each other. Easel does not currently have a feature to connect line segments that are close to each other. This topic might be helpful: Closing dxf file loops-need help converting [SOLVED] - #2 by B.F
Once those 2 shapes are closed, you can make them “Fill” shapes in Easel, set the inner one to a depth of 0, and combine them.