Prepare pudding mixes according to package directions; cool if using cooked.
Blend in 1 teaspoons almond extract.
Combine remaining 1/2 teaspoon almond extract with grape juice in a separate bowl. Set aside.
Spread 1/4 of the pound cake slices with all of the raspberry preserves and 1/4 of the pound cake slices with all of the blackberry preserves; top each spread slice with unspread slice to form "sandwiches.".
Cut sandwiches into 3/4-inch wide pieces. Reserve a few to garnish top of trifle; sprinkle remaining pieces with grape juice mixture.
Spoon 1/3 pudding into 6-cup dessert dish or trifle bowl. Alternate raspberry and blackberry cake pieces in pattern on pudding, using half of pieces. Repeat procedure.
Top with remaining pudding. Cover and chill several hours.
Shortly before serving, whip cream with powdered sugar and vanilla extract until soft peaks form.
Pipe rosettes or spoon dollops of whipped cream on top of trifle; garnish with reserved cake pieces and crushed macaroons.