Hi - it was driving me crazy too. I've finally done it. My tip is to go through all the levels again (make sure you only need this last piece of map otherwise it's pointless), then when you get to the Rapa Nui Special Challenge level that gets you the last piece of map work at it until the timer is just over halfway down and turn the console off. When you turn it on again it will give you another chance and just keep doing this until you get it. The only tip I can give you is that your first move needs to result in the last three icons in the bottom right hand corner being yellow, other colour with yellow above, yellow again. Then when you match the three yellows your map piece will drop.
OK just completed it again and it was slightly different this time, first move get the end column down to two, then use the special moves to clear the last two rows. You will get it, just keep turning the console off before you run out of time and keep at it - Good Luck!
Neptune63: Could you explain exactly how you solved that puzzle? Your instructions are.... unclear. I am TOTALLY stuck on this puzzle and would appreciate ANYONE's help!