Combine gelatin and 1/2 cup water in small bowl until well mixed; set aside. Grease 6-cup mold or 9-inch-round baking pan.
Heat evaporated and condensed milks in medium saucepan; bring to a boil. Remove from heat. Add gelatin mixture, stirring constantly for 5 minutes or until completely dissolved. Stir in remaining 2 cups water into hot mixture.
Divide the mixture in three equal portions (about 2 cups per bowl). Place first portion into prepared mold; refrigerate for at least 1 hour. Stir cookies and cinnamon into second portion; carefully pour on top of first layer. Refrigerate for 1 hour or until set but not firm. Stir in walnuts and Milo into third portion and gently pour onto second layer. Refrigerate for at least 4 hours or until firm.
To Serve: Dip knife in warm water and run knife around rim; gently shake to loosen. Invert onto serving dish.
* May also use about 12 Maria cookies instead of vanilla wafers.