Tiles. Mapmaking problem

Hi!
I have just built a mapmaker program for my tile game.
But i have one problem. I have alot of different tiles.
here it goes:

i made buttons for each category tiles. Like beach > basics and so on.
if i go into the basics frame (this is when i play it, not inside flash), i can go to the beach, to place beach tiles, and so on. much tidier. but when i use the go back button i made, to change tile category, everything on the map disappears…

go back button code:

on (release) {
gotoAndStop(1)
}

SWF FILE

on advance, thank you for any guidence!