It is no longer possible to change loot settings during combat.
10/17/2014: Updated ToC for WoD pre-patch.
1/11/2014: *Untested* Fixed bug after Horridon where trash activates loot master.
9/15/2013: Updated ADDON_LOADED for new folder name to fix default settings.
9/10/2013: Upload for new patch.
9/7/2013: Fixed where I forgot to include the CMMY to be unregistered unless pulling a boss and killing it.
8/29/2013: Cleaned up the code. 8/29/2013: Changed the way bosses with trigger mobs (Yogg/Kael'thas) set and unset loot. 8/29/2013: Added Horridon to the supported bosses because derp I didn't realize it dropped a mount... don't judge me. 8/29/2013: Added the changes to the options panel for the above change. 8/29/2013: Fixed a couple small bugs (eg. related to some printed messages with lua errors). 8/29/2013: Fixed so that the addon is only active in raids, not in 5 man dungeons (while still supporting parties). Hey hey, no more spam! Sorry! 8/29/2013: Changes to overall addon file structure. 8/29/2013: Applied an untested fix for resetting loot settings on Madness of Deathwing (yeah sorry about this guys, one shot at something once a week is brutal... and I don't have time to do it more than that). 8/29/2013: Logging in or being passed raid lead mid fight should now correctly register boss pulls. 8/29/2013: Fixed where CLEU wasn't be unregistered unless you pulled a boss and it was killed... so it shouldn't waste memory for no reason.
8/17/2013: Lines that should be active to disable functionality outside of raids were commented out during testing. This has been fixed. Sorry, I didn't realize I never put them back! Hope useless spam didn't bug you.
8/15/2013: Interface options display changes. 8/15/2013: Added a button in the options to enable or disable all bosses. 8/15/2013: Added the ability to choose what loot threshold you want to switch to on the pull (uncommon, rare or epic). 8/15/2013: Added the ability to pass loot master to another player instead of yourself. 8/15/2013: Changes were made to switching the loot method or threshold before killing a boss to fix errors and more desired functionality.
8/12/2013: Ragnaros should now revert settings on normal difficulty. 8/12/2013: Begining localizations (looking for translations). 8/12/2013: Reverting settings on Deathwing is still being worked on. It may work most of the time from what I gather the problem is but I can only kill this so many times a week to try new things. Hang tight! 8/12/2013: Removed tentacle triggers on Deathwing. It should set the loot without them. 8/12/2013: Switching lead during combat requires more testing.
7/29/2013: Removed message when not group leader. 7/29/2013: Disabled functionality for arenas, pvp, scenarios and LFR. 7/29/2013: Enabled switching settings during combat if a player logs in mid-fight or is passed raid lead mid-fight.