Press whole almonds on diagonal into crust edge, spacing 1/2 inch apart.
Pierce crust all over with fork.
Freeze 10 minutes.
Line with foil and beans or pie weights.
Bake crust until sides are set, about 15 minutes.
Remove foil and beans.
Bake until cooked through and pale golden, covering edge with foil if nuts brown too quickly and piercing with fork if crust bubbles, about 10 minutes.
Transfer to rack; cool.
Spoon filling into crust; chill.
Reserve 1/4 cup berries.
Transfer remaining berries to processor; puree.
Firmly press puree through sieve into measuring cup.
If necessary, stir in enough reserved juice to yield 1 cup.
Transfer 1/2 cup puree to saucepan; mix in creme de cassis.
Sprinkle gelatin over.
Let stand 15 minutes.
Add sugar.
Stir over medium-low heat until gelatin dissolves and mixture begins to simmer, about 2 minutes.
Mix in remaining 1/2 cup puree.
Chill just until cold but not set, 30 minutes.
Spoon topping over filling; chill until set, at least 3 hours and up to 1 day.
Garnish pie with whipped cream and reserved berries.