I have discovered they only show 1 gold coin in freeplay. So let's backtrack on the first floor, did you use a Navy crew to open the door and place 3 different coloured trays on the table one at a time?
When you jumped out on the chandlier, did you use a dutchman character and go through and use a grapple character to open a chest?
Also did you turn the wheel and open up a slot machine and play it and receive a gold coin? At the end did you use an axe character and have it show a rope to climb up and either another ship bottle or gold coin?
Go through the doors and use a super strength character to cause a ball to roll down the stairs and another check mark. Move the statues in place and open another door to go through. After breaking a red chest another checkmark appears. Finish the are and shoot the cannon and jump through the window. In another area, use superstrength character to open a door, open the chest and another checkmark. Play the dice and another checkmark appears. Build the pirate tool and retrieve the guitar and go back downstairs.
Break the legos to build the little box to go upstairs in. But before that use a dutchman character and go through and open a chest for another checkmark. Now use the box to go upstairs to have another duel. Use a grapple character and swing across. Break the barrels and another checkmark appears. Push the barrel over and there is the level.