In large bowl, stir together flour, sugar, dry milk powder, baking powder, lemon peel, and salt. Using a pastry blender, cut in shortening until mixture resembles coarse crumbs.
In 1-quart jar alternately layer flour mixture and dried blueberries. If necessary, add additional dried blueberries to fill small gaps. Seal; store in cool, dry place for up to 1 month or in refrigerator for up to 6 weeks.
Preheat oven to 400 degrees F. In large bowl, combine one egg and 1/4 cup water. Add scone mix from jar; stir just until moistened. Turn dough out onto lightly floured surface. Knead by folding and gently pressing dough for 12 to 15 strokes or until nearly smooth. Pat or lightly roll dough into 8-inch circle. Cut into 10 wedges. Place wedges 1 inch apart on ungreased baking sheet. If desired, brush tops with milk and sprinkle with coarse sugar. Bake for 12 to 15 minutes or until golden. Remove scones from baking sheet. Serve warm.