In a bowl, combine the rhubarb, apples, egg, sugar, syrup, nutmeg and cinnamon. Pour into a greased 2-qt. baking dish. In another bowl, combine the flour, brown sugar and salt. Cut in butter until the mixture resembles coarse crumbs; sprinkle over fruit mixture. Bake at 350° for 45-55 minutes or until bubbly.
If using frozen rhubarb, measure rhubarb while still frozen, then thaw completely. Drain in a colander, but do not press liquid out.