Saute scallops in a small amount of butter or margarine until done. Drain on paper towels and refrigerate to chill. Cut water chestnuts in half, cut cauliflower into bite size pieces and combine with chilled scallops, tomatoes, shrimp, olives, water chestnuts; set aside. Combine all ingredients for dressing and pour over the salad. Mix lightly but well enough to coat everything. Refrigerate overnight or at least 4 hours. Note: This is also good without the scallops.