Removed a line in CommandEndDungeonCreation that inserted a new dungeon directly into DungeonHelper.customDungeons. This had a chance of causing a duplicate listing. registerCustomDungeon() was already being invoked before and if reading tags from the file name failed, the dungeon would get added twice. This could explain some of the buggy dungeon listing that would appear during testing.
DimDoors
Dimensional Doors for Minecraft Adds several items that allow the player to move between and create dimensions
see the MC forum topic for details