Does the original skin have a seam when you use it? And when you say seam do you mean a white area where the textures don't quite meet or  where lines/colors don't match properly? And actually seams are a big problem when painting textures from scratch. One reason is that face textures are quite large in comparison to the body texture and how much it covers. Also the map isn't always as exact as we like to believe it is.

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