Prepare the dressing for this dish. Microwave lime in a small bowl for about 30 seconds to release essential oils, and set aside until it is just cool enough to handle. Through the feed tube of a running blender add, 1 at a time, orange juice, rice wine vinegar, garlic, 2 tablespoons of the orange marmalade, to taste, (you will use the rest if, after you taste it, you decide it needs to be sweetened) and the juice from the now slightly cooled lime. With the blender still running, add the olive oil in a slow stream. Adjust flavor to your liking with additional orange marmalade, if necessary, and season with salt and pepper, to taste. Set the dressing aside briefly.
Prepare salsa by combining pineapple, jicama, red onion, cilantro and jalapeno. Add enough dressing to coat, and reserve the rest to dress the macaroni.
Bring a large pot of salted water to a boil and cook the macaroni al dente. Drain well and set aside.
Season the shrimp with crab boil seasoning.
While the pasta is cooking, heat olive oil over medium-high heat in a large saute pan that will be large enough to accommodate the cooked pasta. Saute scallions and garlic until tender, and then add shrimp and cook until pink and opaque, then remove to a utility platter. (Do not overcook the shrimp.) Remove the saute pan from the heat and add the cooked macaroni to the pan. Stir in Parmesan, and add enough of the remaining dressing to coat. Fold in the salsa and the shrimp, reserving a few of the shrimp for garnish. Season with salt and pepper, to taste, if needed.
Transfer to serving dish and garnish with reserved shrimp and cilantro leaves. Serve any remaining dressing on the side.