How I did What

Template specific images are stored NOT in the /img folder, BUT inside each module folder. So you can edit the images from the administration panel. Go to MODULES >> modules If you want to edit Slider images, select 'image slider for home page' and use 'configure' button  Use the 'Enable/Disable' button and 'Edit' button to edit image. Use the + button to add a new slide.  THERE IS AN ALTERNATE WAY TO CHANGE IMAGES.  You will find all image files in the following folder. Use ftp to download/upload. modules/homeslider/images If you want to edit other images in default-bootstrap theme, select module/themeconfigurator/images If found useful, bye me a coffee for the time you saved.

It is a common problem that though you upload a transparent logo into Prestashop ecommerce site, you end up getting a logo with white background. This happens because the uploaded image is converted to .jpg format by default. Solution Go to Preferences >> Images  Find 'Image format' Select 'Use PNG only if the base image is in PNG format.' Then upload the .png logo again.  Cool! If found useful, bye me a coffee for the time you saved.