Prepare the orange, cherry, and lime gelatin in separate bowls, using 1 cup of hot water and ½ cup of cold water for each flavor. Pour each mixture into individual 8x8x2-inch pans and refrigerate until fully set.

In a separate bowl, combine the graham cracker crumbs with the melted butter and stir until evenly mixed. Press this mixture firmly into the bottom of a 9-inch springform pan to form a smooth crust. Bake at 350°F for 10 minutes, then remove from the oven and allow it to cool completely.

In a small saucepan, heat the pineapple juice with the granulated sugar until the sugar dissolves completely. Take it off the heat and stir in the lemon gelatin until fully dissolved, then add the remaining ½ cup of cold water. Place this mixture in the refrigerator and chill until it reaches a syrup-like consistency.

Meanwhile, whip the 2 cups of heavy cream until soft peaks form. Gently fold the syrupy lemon gelatin mixture into the whipped cream.

Cut the set orange, cherry, and lime gelatin into ½-inch cubes. For best results, dip a sharp knife in hot water before each cut. Run the warm knife around the edges of each pan and use a wide spatula dipped in hot water to carefully lift out the gelatin. The cubes should separate easily and hold their shape. Gently fold these colorful cubes into the whipped cream and lemon gelatin mixture, being careful not to break them. Pour this entire mixture into the cooled crust.

Refrigerate for at least 8 hours or overnight until fully set. When ready to serve, remove only the sides of the springform pan. If you like, whip the additional 1 cup of cream with ¼ cup powdered sugar and use it to frost the sides of the cake. Alternatively, pipe decorative swirls on top using a pastry bag fitted with a 1M tip.