Ever since Zelda: A Link to the Past, treasure chests have been an important part of Zelda. The mystique of seeing an unopened chest, the intrigue of not knowing what's inside until you open it, the challenge of solving puzzles to even access the darned thing, all intregal to a proper quest. And, now a reality.
For a time, people faked treasure chests with Slash combos. But, this technique had a number of disadvantages:
Well, all this changed with the introduction of a proper Treasure Chest combo type. Further, it's possible to have Locked Chests, which require a spare key to open, and Boss Key Chests, which can't be opened with out the boss key. Even better, there are also "copy-cat" types, which themselves can't be opened, but serve to create effects upon opening a chest. For example, you might have a barrier disappear when a chest is opened. Finally, they persist, and are saved, so open chests stay open.
To go about using these new combo types, fire up a new quest. The default tileset included with version 2.5 does not have any treasure chest tiles, so you'll need to draw some new ones up. I made these ones, although I'm sure anyone with any artistic ability whatsoever could make better ones:
Anyway, to go along with these two new tiles, create two new combos using those tiles. They should be immediately beside each other, with the closed chest coming first, as you can see in the screenshot. Also, this is the map I will be using as an example.
The first chest, the closed one, should have the "Treasure Chest (Normal)" combo type set:
The second chest, the open one, should be set to "None", and both chests should be impassable (unless you want chests Link can walk through...). Place the chest somewhere on your map (as seen above).
The next step is to pick the item you want to be in the chest. The Room Type (Data->Room Type) must be set to "Special Item", which will enable the Special Item to be set (Data->Special Item). This item will be in the chest.
The last step is to set a flag telling where the item is to be found. By this, I mean the following situation: Let's say you had three chests, one of which has 200 rupees in it. You can put the item in one chest, and make the others empty. This will result in them losing the 200 rupees, as the chests on one screen can only be opened once.
Anyway, set the location with the Armos (->Item) Flag. Put the flag on the chest itself. NOTE: You cannot set the Armos flag as "inherent". It just will not work (applicable as of writing, version 2.5b254).
And, that's it! Your chest is fully functional! If you want to try it out, be sure to set the Green Square, so Link spawns somewhere in the middle of the map, and try it out.

