Combine egg yolks, 1/4 cup sugar, and salt in a heavy saucepan; mix well. Gradually add scalded milk; cook over low heat 10 minutes or until thickened, stirring constantly. Soften gelatin in boiling water; add to custard mixture, stirring well. Stir in orange rind and Triple Sec. Set mixture aside to cool.
Beat egg whites (at room temperature) until foamy. Gradually add remaining sugar, 1 tablespoon at a time, beating until stiff peaks form. Fold egg whites, whipped cream, and figs into custard mixture. Pour filling into graham cracker piecrust. Chill 2 hours or until set.