Units that are pinned during their activation, do not get to complete that activation. correct?

In other words if their activation was to fire but they get pinned do they still get to fire but at the reduced TQ or if they activated to move and are pinned they must move to cover etc but do they get to return fire and the reduced TQ?

A non initiative unit that reacts to a initiative unit but gets pinned in the process, doesnt get to complete that reaction (ie fire at that unit) correct?

They can still fire back, but with a penalty (unless reduced below D6 TQ) - as it says on page 55/56 of FoF:

_________________
Shawn Carpenter
Game Designer, Ambush Alley Games

"I don't wanna be remembered as the guy who died because he underestimated the threat posed by a monkey."

With Irregular units that are shaken then, can they return fire? or must they move into cover and not toward s the enemy?

Nope. If they're Shaken, they're done until the end of the next turn:

_________________
Shawn Carpenter
Game Designer, Ambush Alley Games

"I don't wanna be remembered as the guy who died because he underestimated the threat posed by a monkey."

My gaming group takes that to mean that they can't fire, *period*. I.e. if fired on, they can't participate in a round of fire except to roll their defense dice or, if they have not yet reacted, may attempt to move away / out of line of fire. If they get shaken during a round of fire, it's applied immediately - so if they lost the reaction roll and would fire second, tough luck, no firing back.

Is that the intent of this rule?

Thanks-

That's the intent!

_________________
Shawn Carpenter
Game Designer, Ambush Alley Games

"I don't wanna be remembered as the guy who died because he underestimated the threat posed by a monkey."