I see that, but I wonder why it is not accented in the original image without PicCure+?
I'm not sure how piccure+ works but can imagine that a deconvolution algorithm could easily find that edge as the texture is quite different on both sides of it even if color is similar.
Deconvolution works by finding and accenting edges where there is a change between adjoining areas.
I can see the artifact clearly in the original so would expect that it would accent them in the final rendering.