Lightly coat a 9" x 13" (23cm x 33cm) baking pan with nonstick spray and set it aside. In a separate bowl, combine the apple juice with the dried fruit and raisins. Cover with plastic wrap and microwave for 1 minute, then set aside to cool to room temperature.
Mix together all the dough ingredients except the fruit, and knead on low speed using an electric mixer until the dough is soft and elastic. Gradually knead in the cooled fruit and the reserved liquid from the juice. Allow the dough to rise for 1 hour, covered.
Divide the dough into 20 balls, each slightly larger than a ping pong ball, using lightly oiled hands. Arrange them in the prepared pan in 4 rows of 5.
Cover the pan and let the buns rise for 1 hour, or until they are puffed and the edges are touching. Meanwhile, preheat the oven to 375°F (190°C).
Whisk together the reserved egg white and milk, then brush the mixture over the buns.
Bake the buns for 20 minutes, or until they are golden brown. Remove them from the oven and transfer to a rack to cool completely.
Mix together the icing ingredients, adding just enough milk to achieve a sturdy, pipeable consistency. Pipe the icing in a cross shape atop each bun.