I made some cooldown displays for my rogue, just the skill icon showing up with a running timer in the middle counting down. They disappear when the cooldown is done. Some of them keep blinking during a GCD (maybe every third time I trigger a GCD, not always) even if they're not on cooldown, so far Kick and Dismantle only, none of the other 4 I made.
The behavior is weird: Sometimes it's only the Dismantle, sometimes both, but NEVER only Kick. Sometimes they disappear at the same time, sometimes Dismantle stays up for about half a second longer. Both timers say 99 during their short appearance. They're inside the same Aura, as different displays, with inline timers in both. Kick uses Dismantle as a parent display for positioning.
Having Ignore GCD / Ignore GCD End ticked have no effect.
Edit. This seems to be fixed when clicking off "Usable" (of course, since I'm using the "Spell off Cooldown" -trigger inverted). Doh.
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As for general usability: having Apply/Accept/Yes buttons on the right side of Cancel instead of the left feels quite counter-intuitive for me, and I often end up cancelling stuff I don't intend to :P. Might just be me, but feels like in various places those buttons are the "wrong" way around.
Also, some of the defaults feel weird. Like having timers with Digital w/ background, I don't think I'd ever have a use for it. And textures having blend defaulted to "none" instead of "glow". Of course again, personal preferences for me.
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I've already grown fond of using the different auras as containers for several displays, a clever way of doing grouping I guess. Much prefer it to the old way of having a ton of single auras ( I think I ended up having close to 100 on my rogue in cata). Just having a "copy" button when viewing the root of a display which duplicates that display inside the aura would suffice for me, that's pretty much how I used it in the old UI as well. So in the way I'm using it now, being able to copy full auras would be useless, but copying displays would be. Well, awesome
Edit: Bug: Sometimes the "Parent Display" -list in display positioning doesn't show anything until you scroll back and forth, I think this started when I hit enough auras for it to become scrollable.