images don't display

Hi,

i've installed, and trying to customize v1.38.
At first I was able to change the zen-cart logo with my own, and used a background image for the body, using the stylesheet.
Then changed a couple of images and their paths (in my custom template folder) and now no images is showing anymore.

I also deleted and re-uploaded the languages, template, and modules folder from the original package, but no luck, even when selecting the classic green template the images don't show up.

I tried changing the background color, but it doesn't change, actually it did the first time, then when I modified the
"Categories Separator between the Category Name and Sub Categories" in admin configuration > layout settings, the background color turned to white and no way in changing it??!!

Thank you.