Do you want the user to interact with sprite in order to get it to move? If not, you can tween a sprite so that it moves up and down exactly the way you want it. Place the sprite at the initial position on the Stage. In the Score window, stretch it out over the number of frames you want for it to move down. Select the last frame of the sprite in the Score window and return to the Stage where you can now place the sprite at its lowest position.
Run the movie over these frames: you can select these frames in the Score and in the Control Panel, toggle on the Selected Frames Only button at the far right. Are you happy with the movement? If not, you can adjust the number of frames for the sprite and choose Modify > Sprite > Tweening to adjust the easing and other properties.
When you like the downward movement, you can copy the sprite and paste it in the following frames, then choose Modify > Reverse Sequence, to make the sprite move upwards. You may also want to reverse any tweening properties.
Finally, you can copy the two sprites and paste them into an empty Cast member slot, to create a Film Loop. If you place the film loop on the Stage, you will get the same animation, but in a single sprite which can be spread over any number of frames.
Try this in the Message window to see a demo of these ideas:
I need to stop it in several positions with a random list of positions and I want to animate in only one frame.