This editor is for Monster Hunter Tri. You must use it with
Riivolution
Open the editor, and then the .bin file.
You get this files here:
MH3Custom
This also work for offline mode!
Qustom Quest Maker: Download
Save the file in the quests folder.
Note:You should save the file anywhere, before you overwrite it!
This editor contents all quests, online and offline, and some extra quests. You can't add new Quests, only edit.