Season some shrimp and grill it for about three minutes, then slice it in half lengthwise. Fill a large bowl with lukewarm water, and dip one rice paper wrapper at a time in the water for eight to ten seconds, then lay the wrapper flat on a damp kitchen towel. Stack up some shrimp, sliced cucumber, avocado, mango, cabbage, and cilantro. Next, start wrapping. Just lift the bottom of the wrapper up and over the filling, press down gently, and roll the wrapper completely around the filling into a tight cylinder, folding the sides of the wrapper halfway through rolling. Dip your finished roll in an optional chile-lime sauce, or enjoy them by themselves.