Goal 12 requires 5 messages in a bottle but the final upgrade to the ship requires 6.
From post #2 on page 1:
Goal 12:
* Make a Message in a Bottle 0/5
* Dress a Look-Out Parrot 0/6
* Prepare a Captain?s Wardrobe 0/6
* Read the Treasure Map |
Level 5: 1 treasure map, 6 message in a bottle, 6 look-out parrot, 6 captain's wardrobe