You can use the Grow/Shrink animation for each image, combined with a Line Animation if necessary to move the image to the right location.

If the animations have to proceed very fast, you can choose 'With Previous' instead of 'After Previous' for the different images, use small Duration times and add very small Delay times to the 'With Previous'.

Note: when you use a Grow animation on a small image, it might look pixelated after growing, even if the originally inserted image is large and you scaled it down on the slide.
To avoid this:
- insert large image
- add Shrink animation 'With Previous', duration 0.1 (to get the thumbnail size)
- add Disappear animation 'With Previous', duration Auto
- add Appear animation 'After Previous' (or Fade, or any entrance animation)
In Slide Show View you will not see the shrinking or disappearing, you will only see the appearing of the thumbnail size.
Now when you add a Grow animation to enlarge your thumbnail, your image will maintain its original quality.

This is how I would build the slide - hopefully you will also receive some answers that give a less complex animation panel and we can both learn from it

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