Readbeard's Booty

hey guys, I need a hand with the quest "redbeard's booty"... ive got to the point where I have 2 maps and 3 "essence of the beast" and I have absolutely no idea what to do next... im fairly sure im gonna need another map piece, and that its somewhere on the island with all the purple blocks... can some one tell me where abouts to look for them?

thanks

 

Did you climb up a mountain to get a map piece?
Did you do a puzzle to get a map piece?

Also, I'm pretty sure you have to put the Essence of the Beast into a hopper on the third island to get another map. A red X should spawn.

 

I missed putting the essence of the beast in the hopper... thanks!