I can't get the last seachart for phantom hourglass.

I haven't played this game much myself, maybe this walkthrough will help you?
http://www.cheatsguru.com/nds/the_legend_of_zelda_phantom_hourglass/walkthrough/1577118.htm

http://tinyurl.com/mxbo39
;)

its probaly a bootleg copy which makes it turn off

i'm using no$gba2.6a. what i did is... i click the southeast map and minimize the emulator

Put the stones in this order Square(middle), Circle(left), then triangle(right)

eat a dog

North Eastern sea, most likely. At least, from what I can recall. The islands surrounded by rocks? Or is it the area with the Gorons? Or the ice dungeon? Try the North EAstern sea.
Also, the last sea chart is likely deeper in the area where you found the others, meaning the Temple of the Ocean King.
Have fun!

to get to the next level you stay on the safe spots til you light the torches.'K.

You have to put the jems in the pedestals in a certain order - (Square - Round - Triangle) then go through the door & you will see that the floor level drops outside - when you go back through the door you are on a whole new set of levels - Enjoy!

an hourglass