I am guessing that you imported your layered AI file as a composition. If that is correct here's the steps that make your project easy.
- Import as a composition retaining layer sizes
- Open the comp created when you imported the AI file
- Move the CTI to the point in the timeline where you want the animation to end
- Select the anchor point tool and set the anchor point of each layer at the point where you want the layer to scale or rotate
- If you are going to use 3D moves make all the layers 3D at this point
- Press Alt/Option + p, then Alt/Option + s, then Alt/Option + r to set keyframes for the resting (hero) position
- Move the CTI (current time indicator to the start of the animation and then re-position each layer to their starting position
- Adjust the timing of each move as required
There you go. There is no reason to not start at the end and move backwards. Whenever I prepare artwork for video in Illustrator I always arrange the artwork in the hero position so that animation is easy. No matter what kind of composite of visual effect you are working on it's usually easier to start laying out the scene on the hero frame and then work backwards and forwards from there.
How do you intend to animate this Illustrator work? Being specific helps. From the looks of the layers, I don't see a whole lot that can be animated.
Did you ever finalize this animation? How did you end up doing so? Did any of these responses assist you? Or do you still need help? Please let us know.