On work surface, place 1 roll-up with short sides at top and bottom. Spread 2 tablespoons cream cheese over entire surface of roll-up. Spread 3/4 cup cooled rice over cream cheese, leaving 1 1/2 inches of top short edge free of rice. Starting 1 inch from bottom short edge, arrange narrow row of carrot, row of bell pepper and row of crabmeat crosswise over rice. Above crabmeat, place 2 onion halves, alternating ends so there is one green end and one white end on each side. Press all layers into rice.