I'm going to set aside my INTENSE curiosity regarding the logistics of procuring materials, acquiring skilled labour, building suitable facilities, and distributing parts, etc, considering the available infrastructure in Kabul! You are ambitious!
I suppose you're involved with an NGO.
Hugh Piggot has already published manuals geared specifically for your task. Several designs can be chosen, and scaled according to your needs, too.
To answer your specific question (briefly), the blades of a wind turbine need to be producing lift at a reasonable angle of attack. Looking at the tip of a wind turbine blade, it should be traveling around the axis at, for example 6 m/s in a wind of 1 m/s. But half-way down the span of the blade, that's only moving at 3 m/s in the same wind. If the airfoil at the tip is inclined at its optimal angle of attack, then it won't be half-way down, unless there is some twist to make up for the slower rotational velocity as you get closer to the axis.
Glauert was an aerodynamicist from the early half of the 1900's who figured out an awful lot of the aerodynamics that we consider "obvious" today. A "Glauert twist distribution" probably means a twist that conserves the angle of attack through the span of the blade, however Mr. Glauert was subtle enough to have also been aware of tip effects, and maybe adjusted twist at the tip to account for that, too.
I don't know why the researchers in the studies you posted would have recommended an S823 airfoil for such small wind turbines (as low as 1kW). Say the wind turbine you propose to build has a diameter of 12 feet (3.6m). The chord of each blade (3 blades) would be about 7.5 inches. At the tip, the chord should taper down to about 5 inches.
At this scale, the difference between the Selig 822 airfoil and an "ancient" NACA is very small. If you were then to compare the performance specs of these two airfoils, carefully considering scale effects, you would find very little difference in the end result. It might matter in a bigger turbine, but not a small one.
Worse, the S823 has a nasty concave curvature at the trailing edge, that will be much more difficult to control than an airfoil with all convex curvatures.
If you're going to be responsible for the detailed aerodynamic design of a wind turbine, that people will be investing money and livelihoods into, I strongly suggest you get some aerodynamics books and take a few seminars!
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Good luck.
Steven Fahey
