Animating a NPC

Hello everyone, I am making a deathrun map, and I have hit another bump in the road.

For a trap, I wish to make it so that a heavy shoots at a few props, and ultimately "breaks" them, allowing him to unintentionally kill whoever is within the trap area. And after this, and engineer pops in to "rebuild" the props he destroyed.

Questions:
How do I make the Heavy appear to shoot his minigun?
How do I make the Engineer appear to rebuild the props? (Much like building a sentry)
To make the props "break" and then reappear, should I just set an output in the trap button to enable/disable?

I have made a prop_dynamic with the heavy model, but what is tripping me up is the animation part. The default animation box is a type-in box, not a drop-down menu, so i have no idea what to even type in there.

Actually, I found that "model" tab right after posting this, but the animation I need is broken, it just makes the heavy lie down on the ground and sort of shake. I had to rethink the trap because of this. Quite disappointing really.

How do I do that, it only allows me to set one animation.