Here is the full list of all 38 Castaway Paradise Complete Edition achievements.
Rebuild Victoria's Mansion
Unlock the second room in your house
Live the luxury life of a VIP
Rebuild Francis' Pirateshack
Remove 25 cobwebs
Donate 15 fish
Completed 100 quests
Donate 15 shells
Unlocked a gate
Make a profit of 500 gems on the Stock Market
Collect 25 pieces of garbage
Changed every piece of outfit
Donate 15 bugs
Remove 50 weeds
Harvest 50 crops
Remove 25 stones
Used every piece of equipment
Rebuild Gustave's Bakery
Donate a collectable
Rebuild Harold's Museum
Rebuild a bridge
Completed 25 quests
Get your first collectable
Completed the tutorial
Donate all bugs
Donate all fish
Donate all shells
Donated every collectable
Read 50 chit chats
Rebuild Amelia's Planehouse
Rebuild Angus' Trailer
Rebuild the Lighthouse
Make a profit of 5000 gems on the Stock Market
Make a profit of 2000 gems at the Bank
Grow every type of fruit
Grow every type of flower
Grow every type of crop
Wore an outfit of the opposite gender