Combine cranberries and orange (rind and all) in a food processor and pulse until finely chopped.

In a medium heat-proof bowl, dissolve Jell-O in the boiling water. Add cranberry mixture and stir to combine. Refrigerate until partially set, about an hour.

Stir in pineapple with its juices, celery and walnuts. Pour into a mold or 8-inch square dish and refrigerate until set, about 3 hours more.

To unmold the gelatin, run a butter knife around the edge of the mold, then dip in enough hot water to come about three-quarters of the way up the sides for about 10 seconds. Wet the plate or tray you will be serving it on (this will help slide it into place) and place the plate on top of the mold. Invert the mold and shake gently to loosen. Slide gelatin where you want it on the plate and serve.