Heat oven to 350~F; grease 10-cup fluted tube pan, preferable Teflon coated. In large bowl combine flour, sugar, cocoa powder, grated orange peel, baking soda, cinnamon, nutmeg, oil, eggs, and orange juice; with electric mixer at low speed, beat just until blended. Increase speed to medium; beat 2 minutes until blended and smooth. Stir in carrots, raisins, and chopped walnuts. Pour batter into prepared pan; bake 45-50 minutes until wooden pick inserted in center comes out clean. Cool cake in pan on wire rack 15 minutes; remove from pan to rack to cool completely. Meanwhile, in medium size bowl mix at medium speed, beat cream cheese, powdered sugar, 2 tablespoons milk and vanilla until blended and smooth; remove 1 tablespoon to small bowl. To mixture in medium bowl, add cocoa powder and remaining 1-2 tablespoons milk; beat until smooth and of proper consistency for glazing. Spoon chocolate glaze over top of cooled cake so glaze drips randomly down sides; drizzle plain glaze over chocolate to serve.