Combine the sugar and salt in a mixing bowl until evenly mixed.
Stir in the orange zest, chopped fresh dill (or the herbs you have), a few grinds of black pepper and the grated beetroot; mix thoroughly.
Pack the curing mixture over both salmon pieces so they are completely covered, then place the fish in a shallow container and weigh it down with a plate or similar to ensure contact.
Cover and refrigerate for 24 to 48 hours depending on how cured you want the salmon (24 hours for lightly cured, up to 48 hours for firmer cure).
Remove the salmon from the cure and rinse thoroughly under cold running water to remove all salt and sugar, then pat dry with paper towels.
Thinly slice the salmon across the grain into serving slices and set aside.
Peel the cucumber, remove the watery center, and dice into small pieces; toss with a little chopped dill, a splash of vinegar, olive oil, salt and pepper.
Using a sharp knife, peel and segment the orange, removing all membrane, and reserve any remaining juice in a small saucepan.
Bring a small pot of water to a boil and gently add the quail eggs; cook for about 45 to 60 seconds for very soft centers, then transfer to an ice bath to cool.
While the eggs cook, simmer the reserved orange juice to reduce to a glaze, then season with a pinch of salt, a squeeze of lemon juice and finish with a little olive oil.
Peel the cooled quail eggs and halve or leave whole as desired.
Arrange the sliced gravlax on plates, top with the dressed cucumber, orange segments, quail eggs and a few sprigs of fresh dill; drizzle the orange glaze alongside to serve.