Place chocolate wafers in the workbowl of a food processor and pulse to form crumbs. Or place the cookies in a closed plastic bag and roll with a rolling pin to form crumbs. In the processor or in a bowl, combine the crumbs with all the other ingredients and pulse or toss until the crumbs are evenly moistened. They should hold together well when squeezed between your fingers; add a few drops more liquid if needed.
Press the crumb mixture into eight 3 to 4-inch heart shaped tartlet molds, oven-proof Pyrex or metal, and refrigerate them to set while you prepare the filling.
Measure the yogurt into a cheese cloth-lined strainer set over a bowl and drain for about 30 minutes/ you should have about 1 1/4 cups of yogurt. Discard the liquid (or drink it, it is high in calcium).
Halve the strawberries and set aside.
In a food processor or blender, mix together quickly the cream cheese and sugar. Add the drained yogurt, halved berries, preserves, Chambord or cassis if used, and salt; pulse to blend but do not puree completely-there should still be some pieces of berries.
In a small nonreactive saucepan, combine the orange juice and lemon juice. Sprinkle on the gelatin and let stand for about 3 minutes to soften. Stir the mixture over low heat just until the gelatin dissolves; do not boil. Remove from heat and stir in a few tablespoons of the strawberry cream to cool the gelatin. Then pour the gelatin mixture into the strawberry cream and pulse or stir to blend in. Fill the tartlet molds. Chill at least 3 hours, or overnight. Before serving, garnish each tartlet with a whole fresh strawberry or slices fanned out, or a mint sprig.