OR...you could make a chest like this:

1. Make a fork condition and set it to:
Event "this Event" - "Down" Face Dir
Do not check else case.

** INSIDE THE FORK CONDITION **
2. Play Sound Effect (optional) - Open Chest
3. Set Message Style (optional) - Normal, Down, Nothing checked
(* Below can be anything you wish. Whatever you want to be found in the
chest *)
4. Change Gold Held - Increase - 25gp
5. Show Message - You found 25gp.
** END OF THE FORK CONDITION **

6. Move event: this event, face left

(thanks to JDBoone)