Animation Stops instead of loop?

[Amnesiaplayer]

So I recently tried to create an entity.
It's a skull, High detailed skull (it's 4mb :O)
So I thought, why not make some animations, halloween is close, I'd like to share this skull with you
I tried to do 3 animations.
First is just his mouth going up and down, (yeah 2 seperate parts, head and mouth)
second is "eat" animation, This is a kind of problem, because I want this to happen if you do something, that the animation starts, so is it possible to make the animation happen by script?
Like The skull is normal, if you collide a cake, to an area, then his "eating" animation starts... If yes, How?! haha

And the other problem of the animation is, it stops.
In maya, it goes like up and down up and down etc.
In amnesia it constantly Re do it (wrong)
So the animation is supposed to go up and down. (loop)
But modelview shows it like up and down, directly being up, and then goes down, directly starts from up again and then go down etc..
Hopefully someone will understand xD
My English sucks I know

So basically, I want an animation to loop, and want to know how to make it Start, and stop. (start the animation from script, and make it do once and then stay normal as before)
and I want to know how to fix that shitty thing
Instead of "loop" it just re-do everything in modelview...