Heat grill to high, and spray with cooking oil. Sprinkle salmon with salt and pepper, and and grill salmon, skin side down, for about 10 minutes, or until cooked as desired. Remove from heat and let cool.
Place greens, walnut pieces, grapes, pomegranate seeds in a large salad bowl and toss well.
While salmon is cooling, make the dressing, but placing avocado, citrus juices, orange zest, olive oil, dijon mustard, and honey in the bowl of a food processor. Process until smooth. Add salt and pepper to taste, and water if needed, to thin.