A little slow in the execution

[RavenSaint]

New to nUI. My husband (using nUI from Curse) noticed that there is a little bit of a lag between activation of the ability to the execution of the ability since the last patch. He wasn't sure if that was Bliz/compatibility issue or just a minor bug that came up with the last patch changes/updates?

Here are the addons we use for RP servers (most of these are popular with majority of RPers):
(incase there is addon compatibility issues for RP addons)
My Roleplay (MRP, Others are FLAG and IRP)
Tongues
NotesUNeed
Cartographer
Gatherer
Considerator (Gear comparison and suggestion addon)
Mapnotes (Mapmod adding map icon libraries and more details to mapnotes)
Raidtracker (Guild Raid Loot tracker and attendance addon)
Nirriti's ActionColorButtons (very old Addon, had it for 4 years now and it still works)
Deadly Boss Mods
zBar3 (unused, currently awaiting updates for the Mod as the project has been dropped by Zerofire 1/2009, I was one of the US testers for it, but it was hard to talk between the Japanese/Chinese net and US/EU net, was a nice light UI mod that allowed for moving, resizing, and customization of the Actionbars removing the clutter of the UI frames and graphics, miss it alot for my casters)