HEAT oven to 425ºF.
MIX flour and sugar in large bowl. Cut in butter with pastry blender or 2 knives until mixture resembles coarse crumbs; press onto bottom and 1 inch up side of 9-inch flan pan. Bake 12 min. or until golden brown. Cool completely.
BEAT pudding mix and milk with whisk in medium bowl 2 min. (Pudding will be thick.) Add Cool Whip, zest and juice; mix well. Spread onto bottom of crust; top with berries.
MICROWAVE marmalade in microwaveable bowl on HIGH 30 sec.; stir. Spoon over berries. Refrigerate 1 hour