Mix bread crumbs, 1/4 cup cornstarch, and coconut in a deep bowl and set aside. Combine Pina Colada mix,powder sugar and Rum in a small mixing bowl and set aside. Place 1/2 cup corn starch in a separate bowl. Heat oil for deep frying. Oil is ready for frying shrimp with it reaches 375 degrees. Coat shrimp first in corn starch, then into the Pina Colada mix, then dust shrimp in bread crumbs, coconut mixture. Second coating place back into Pina Colada mix, then again into coconut, and then the bread crumb mixture. Place prepared shrimp carefully into hot oil. Fry until golden brown, remove from fryer and drain.