In a bowl, combine the papaya and lime juice. In a small saucepan, combine the sugar, pineapple juice, and orange juice and bring to a boil. Reduce the heat and simmer, stirring, until the sugar dissolves. Add the marinated papaya and simmer until tender, about 7 minutes. With a slotted spoon, transfer the papaya to a bowl and set aside.

In a small bowl, combine the cornstarch and water, stirring to dissolve. Add to the simmering juices and whisk. Add the lime and orange zests, and cook over low heat whisking until the mixture thickens, stirring occasionally. Remove from the heat and add the papaya. Add the butter and stir until melted. Let cool. Pour into the prebaked shell. Refrigerate until set, about 2 hours.

In a medium bowl, whip the cream and sugar until soft peaks form. Add the rum and whip until stiff peaks form, being careful not to overwhip. Top with whipped cream and sprinkle with the toasted coconut. Arrange the lime slices in a decorative pattern and serve. Refrigerate any leftover pie.

In a bowl, combine the butter and sugar and blend to make a paste. Add the yolk and blend thoroughly. Add the flour and using your fingers, blend to make a crumbly dough, being careful not to overwork. Pat firmly into a 9-inch pie pan and let rest in the refrigerator at least 2 hours or overnight. Remove from the refrigerator and prick the bottom of the crust with the tines of a fork. Place a sheet of parchment or foil in the pie tin and fill with pie weights, dried beans or rice and blind bake the crust in a preheated 400 degree oven for 10 minutes. Remove the pie weights and foil and bake for another 5 minutes or until light golden brown.