I'll pick a few aspects of the interface to complain about

(not in any particular order)
1) Moving the HUDs around.
- (a) Get rid of all the chat spam when doing it.
- (b) Actually move the HUDs as they're being dragged, so you can see where they're going.. and don't jump the top-left corner to the mouse's coords when you start dragging them.
- (c) Make them only draggable by the title, and dont eat the mouse messages (not sure if you actually do that currently).
2) The interface for setting up which salvages to loot is pretty hard/annoying to use. Have the list show all of the salvage types (don't make you add them 1-by-1) and maybe even make clicking the name show a description of what it does (ala ElTank). Then you can set the min workmanship by clicking on the number in the list (again like ElTank).
3) Move Loot to a top-level tab and move the "Filters" tabs directly under the Loot tab (getting rid of the "Filters" tab). You can get rid of the "Magicals" tab and add wands to the "Weapons" tab. It also seems like Exceptions should be on the same tab as Salvage, but I'm not sure if it'd fit.
4) Most people I've talked to didn't know what Y, I, V, and P meant on the Macro > Mobs tab. Even a [?] button next to them that will print out a description when you click it would work: "

= yield, I = imperil, V = vuln, P = priority (higher priority number means attack first)".
5) Put the route editor directly in the Nav tab instead of a second window (not really a big problem).
Also a few non-UI aspects:
1) Share loot profiles between characters.
2) Seriously improve the buffing logic - it's rather brain-dead right now.
- (a) Number one priority should be that the character is actually buffed when LTx thinks he is. That means checking the buffs on the player and manually keeping track of item buffs.
- (b) Changes to the buff cycle length or continuous buffing shouldn't require you to restart the macro, and thus have to do a complete rebuff to make sure LTx doesn't let any of your buffs drop.
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[LotRO] Digero (Guardian), Digrim (Burglar), Dignite (LM), Azrea (Hunter) - Landroval
[AC] Digero, Lyera, Draxxe - Leafcull (Retired)
[CoH] Devil's Zealot, Scinta, Izzard - Guardian (Retired)
Digero's AC Decal Plugins:
http://decal.acasylum.com