Hi Mischa
You can do this using any composition. So lets say Project 1 , Project 2 and Project 3 has different images which you want to show up when any one the thumbnail is clicked.
Insert a composition , like tooltip , add the image for thumbnail in trigger and then insert slideshow in target container where you can add the images for project in slideshow. This way when users will click on thumbnail image , the container will appear on screen with a slideshow showing images for that specific project.
Please let me know if this is not what you are looking for.
Thanks,
Sanjit