Grease a 6cm-deep, 19cm square cake pan. Line base and all sides with baking paper extending paper 5cm above each side.
Place biscuits in a food processor. Process until coarse crumbs. Add butter and allspice. Process to combine. Press biscuit into base of prepared pan. Refrigerate until required.
Place boiling water in a small heatproof jug. Sprinkle over gelatine. Stir until gelatine dissolves. Cool for 5 minutes.
Using an electric mixer, beat cream cheese, sugar and orange rind until light and fluffy. With motor operating, gradually add cream, gelatine mixture and chocolate, beating until mixture thickens slightly. Stir in pistachios. Pour mixture into pan. Refrigerate for 2 hours or until just set.
Make jelly following packet directions. Stir in rosewater essence. Refrigerate for 1 hour or until cold but not set. Pour over cheesecake layer. Refrigerate for 4 hours or overnight until jelly is set. Carefully lift out of pan. Cut into squares. Serve.