Heat oven to 450°F. Bake pie crust as directed on box for One-Crust Baked Shell, using ungreased 10-inch tart pan with removable bottom or 10-inch springform pan, and pressing 1 inch up side of pan. Cool on cooling rack 15 minutes.
Place orange juice in 2-quart saucepan. Sprinkle gelatin on juice; let stand 5 minutes to soften. Stir in 3/4 cup of the whipping cream; heat over low heat, stirring frequently, until gelatin is dissolved. Stir in white chocolate until melted and smooth. Transfer to medium bowl; refrigerate about 30 minutes, stirring occasionally, until cool but not set.
In blender or food processor, place thawed raspberries and any juice. Cover; blend until pureed. Set strainer over 2-cup measuring cup. Press puree with back of spoon through strainer to remove seeds. If necessary, add water to raspberry puree to measure 1/2 cup. In 1-quart saucepan, mix cornstarch and sugar. Gradually add raspberry puree. Cook over low heat, stirring constantly, until thickened. Fold in fresh raspberries; spread over crust. Refrigerate 15 minutes.
Meanwhile, in chilled large bowl, beat remaining 3/4 cup whipping cream with electric mixer on high speed until stiff peaks form. Fold whipped cream into white chocolate mixture. Spoon and spread over raspberry layer. Refrigerate about 1 hour or until filling is set.
In 1-quart saucepan, melt semisweet chocolate and butter over low heat, stirring frequently; carefully pour and spread over white chocolate layer. Refrigerate at least 2 hours until set. To serve, let stand at room temperature about 30 minutes to soften chocolate layers. Cover and refrigerate any remaining tart. Garnish each slice with fresh raspberries and white chocolate curls.