Dissolve yeast in warm water; set aside. In a large mixing bowl stir together the biscuit mix and the 1 tablespoon sugar; add egg and yeast mixture, stirring until smooth. Turn out onto a lightly floured surface; knead 10 to 15 strokes. Roll dough to a 9-inch square. Place on greased or parchment-lined baking sheet.
In a small mixing bowl combine preserves or jam, dates, and nuts. Spread mixture down center one-third of dough. Make 3-inch-long cuts from the edges of opposite sides toward the center at 1-1/2-inch intervals. Starting at an end, alternately fold opposite strips of dough, at an angle, across the filling. Slightly press ends together in the center to seal. Cover and let rise in a warm place until nearly double (about 30 minutes).
Bake in a 350 degree F oven about 20 minutes or until golden brown. If desired, brush with melted margarine or butter and sprinkle with additional sugar. Serve warm or cool. Makes 10 servings.