In Paper Mario: The Thousand-Year Door's root file structure, the game's mail-pictures, crystal star map, save select menu, and pause menu graphics is stored in root/w with one subfolder. Much like the msg folder, the subfolder uses a country code.
The tpl format is a compressed file format that contains .tga files, which can be opened by most graphical editing programs.
Graphics for the pictures included in the mail letters.
There are eight map.tpl files, named from “map0.tpl”, “map1.tpl” and so on. They contain the graphic for the crystal star map, which changes in design as more crystal stars are obtained in-game.
Save select menu graphics.
Pause menu graphics.