Dear Boran,
It is been so long since I wrote that report that I cannot remember the effect of the smoothing, but certainly the stall characteristics of an airfoil are important for pitch-to-stall-regulated turbines.
You can find the smoothed airfoil data in my post dated Sep 26, 2017 in the following forum topic: NREL 5MW Rotor Geometry - #15 by Jason.Jonkman.
Best regards,