Rinse squid, pat dry and cut into rings. Thaw before if frozen.
Peel onion and garlic and finely chop.
Heat 2 tablespoons oil in a saucepan. Saute onion, garlic and ginger. Add squid, season with salt and pepper. Deglaze pan with wine and stock and simmer, covered, on low heat for about 30 minutes. Add shrimp and cook for 3-4 more minutes.
Combine lemon juice and remaining olive oil in a bowl, mix well. Remove squid and shrimp from a pan and toss with lemon dressing.
Peel papaya, cut in half, remove seeds and cut into small strips.
Rinse cucumber, cut in half lengthwise, remove seeds with a spoon, cut crosswise into thin half-slices.
Combine papaya, cucumber, squid and shrimp. Arrange on plates and serve.