Heat oven to 350°F. In food processor bowl with metal blade, process gingersnaps and chopped pecans until mixture is finely ground. Add butter; process until mixed. Press mixture in bottom and 1 inch up sides of ungreased 9-inch springform pan. Bake at 350°F. for 8 to 10 minutes or until edges are lightly browned. Cool 30 minutes or until completely cooled.
In large bowl, combine softened ice cream, nutmeg and rum extract; stir until blended. Spread evenly in crust-lined pan. Place pecan halves around top edge of torte. Cover dessert; freeze at least 4 hours or up to 2 weeks.
To serve, let dessert stand at room temperature for 15 minutes. Run knife around edge of dessert; remove sides of pan. Cut into wedges to serve.