Process almonds, peppers, tomatoes, garlic, oil, vinegar, paprika, 1/4 teaspoon salt and 1/4 teaspoon pepper in a food processor or blender until smooth; set aside.
Coat salmon and zucchini (and/or summer squash) on both sides with cooking spray, then sprinkle with the remaining 1/2 teaspoon salt and 1/4 teaspoon pepper. Grill, turning once, until the salmon is just cooked through and the zucchini is soft and browned, about 3 minutes per side.
Transfer the zucchini to a clean cutting board. When cool enough to handle, slice into 1/2-inch pieces. Toss in a bowl with half of the reserved sauce. Divide among 4 plates along with a piece of salmon topped with some of the remaining sauce. Garnish with parsley, if desired.