Quote:...My problem seems to be with the foreground selection method. It seems to bring over some of the edge outside the selection.....
The Foreground Section tool is not wonderful, as you found. My preferred method is a layer mask and then paint out any excess / missing areas.
..but.. If you want to use a selection a better way (and depends on how complicated the shape is) Use a path. Put the path to a selection. Shrink the path a pixel or two to get away from the border pixels, Invert and cut.
You could try the Selection -> Shrink with the FG select tool result before inverting It might / might not be a fix.