I think I've found a way to robustly transfer vector artwork from Illustrator to Eagle. Below I show an “amoeba” vector shape in Illustrator being converted and used as a board outline in Eagle. …. Nice tutorial , I particularly like the generality. As you say, the concepts should work with other SW as well. Isn't there an option when exporting to export as straight line segments rather than “curves” (thereby avoiding the need to add the extra anchor …

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From Illustrator to Eagle: Vector graphics in circuits « todbot blog