A surface normal is calculated using only the first three vertices of a surface.
The vertex order only really matters if you have a concave polygon i.e. one with a 'dent' in the side. If that 'dent' is defined by the first three vertices, the normal will be the opposite to what you expected - and you may get a black surface (because the lighting gets confused).
A red outline on a surface either indicates crossing edges (move some vertices) or that it failed to triangulate - possibly because the vertices are not on the same plane.
Andy
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