In large bowl, combine Graham crumbs, pecans, sugar, cocoa. Stir in butter. Press mixture onto base of greased 10-inch spring-form cake pan, pressing mixture slightly up sides. Bake at 350 degrees for 12 minutes or until golden brown.
In a small bowl, combine 1/2 cup sugar and gelatin. Stir in lime juice and rind. Set aside to soften. In a medium saucepan, heat coconut milk. In a medium bowl, whisk egg yolks with 1/2 cup sugar until lemony. Whisk in the hot coconut milk. Return mixture to saucepan. Cook stirring constantly, over medium heat to the consistency of thin custard. Do not boil.
Stir in gelatin mixture with rum. Cool to room temperature. Beat cream cheese. Blend in coconut mixture. Cover and refrigerate for one hour or until barely set.
Beat egg whites to soft peaks. Add sugar, and beat until stiff. Gradually fold into the prepared mixture. Pour into crust. Refrigerate 2 hours.
Puree raspberries with sugar. Strain to a sieve. To serve: Loosen edges of tart. Remove side of pan.
Decorate with lime slices.