It's odd. I now about the global cooldown, this had a No Target type prompt when I tried to use a skill that wasn't on a cooldown. I'll give an example:
A fellow Smuggler was closing in on me, nothing is between the two of us. Open space.
I hit my Hemorrhaging Blast skill, it does the flicker to let you know you hit that skill.
Nothing happens. Doesn't fire.
Hmm.
I look and make sure I'm hitting the skill again, same result.
Ok, nothing. Let's try Flurry of Bolts. Damn.
Eat floor.
The End. Cheers.
Very, very strange I say.