Prepare rice according to package directions. Stir in vinegar; cover and cool to room temperature.
Combine wasabi and avocado in a small bowl, and set aside. Combine cilantro and shrimp in another small bowl; toss well.
Cut off top quarter of nori sheets along short end. Place 1 nori sheet, shiny side down, on a sushi mat covered with plastic wrap, with long end toward you. Pat 3/4 cup rice mixture evenly over nori with moist hands, leaving a 1-inch border on one long end of nori. Spread 1 tablespoon avocado mixture over rice.
Arrange 8 shrimp pieces, 2 chives, and 2 cucumber strips along bottom third of rice-covered nori.
Lift edge of nori closest to you; fold over filling. Lift bottom edge of sushi mat; roll toward top edge, pressing firmly on sushi roll. Continue rolling to top edge; press mat to seal sushi roll. Let rest, seam side down, for 5 minutes. Slice crosswise into 8 pieces. Repeat procedure with remaining nori, rice mixture, avocado mixture, shrimp mixture, chives, and cucumber.