Replacing images of Lightslider plugin

Hello, I'm slowly getting familiar with Grav and testing things that work more or less well, and now I'm stuck on something, here is :
I loaded the skeleton "shop" and I try to modify the slider but I miss something to make it work, example:
(I specify that I work with Atom in parallel)

• I tried to delete the third image of the slider and replace it with one of mine, so in user/pages/slider I deleted the file "image-3.jpg" then I pasted in this folder an image from my personal folder instead, I then modified the file "blog.md" by deleting the image-3.jpg to write the name of mine instead.
  Apparently that's not enough, can you tell me what I forgot to do, I guess something is missing from the "lightslider.html.twig" file but I don't see where to change it, but it might not be that at all thanks in advance. jef

I found how to do it, it was necessary to modify on the file .md and on the one of "lightslider.yaml" the option "text" and to pass it to "image", on the other hand I have a question about the images to be included in the slider; it is necessary to modify its images before installing them in the folder "slider", or if not is there a place where to regulate the final size of the images of the slider?
thank you in advance.jef

This topic does not correspond exactly to its title anymore, so I moved it here: Lightslider change the height of the scrolling slider in image mode***

Hi Jefrey

1. What .md file did you change and where?
2. Can you please provide a step-by-step guide on how to change the slider images?
3. We usually adjust all images to the same height as we like them to appear in the slider, though it is possible to upload also much bigger images, and then the center area gets chosen. It is simply way to difficult to adjust the images as there seems to be no option to move around the image up and down and resizing it like you usually do when positioning images on social media. In HumHub you can do it too and then the image gets processed and cut exactly to the size you have chosen.. But in HumHub you can actually upload a huge image and then choose a detail out of it. Probably check out how it is done there!