This is very tricky.
I see fluid height in a group is not working like in the slider, for desktop (Mobile version works fine).
Group considers the width of the screen and not the height.
Hence, images will display very different depending on the size / ratio of the screen.
(ie: Tablet 768×1024, HD 1920×1080, iMac 2560×1440).
I can’t find a module columns width that will display “ok” in all resolutions.
I will need to find a solution so that images display good in every screen…