oRA2 must be installed for this module to function.
When you are the raid leader, oRA2_Difficulty will automatically set the dungeon difficulty shortly after the raid is formed. Defaults to 25 Player, although if you usually run 10 mans you can set that. Auto setting 10 or 25 Player Heroic is also available.
This module is only really useful for forgetful raid leaders (like me) who always forget to check the difficulty setting.