Black Box Problem

The problem is just a black box.
My images are saved on www.buckcraft.com/images/screenshots .
A test image I made is www.buckcraft.com/images/Screenshot.png
So as folder I filled in images/screenshots
and as Image Name i filled in Screenshot.png

What am I doing wrong?

BTW: I'm using Joomla 3.0
Do I need to set the module in a special position. (It's now in user1.)

Then:

"Folder where your images are stored" should be just: images/

if Screenshot.png is on right place

It didn't work
I changed "Folder where your images are stored" to images/
But it just stayed black.
can it happen that the image is too big?
Screenshot.png is in the folder images and in the folder screenshots.
I tried both folders but it stayed as a black box as you can see on www.buckcraft.com .
Does it has to do with the width and height?

Oh this is interesting when I change the slider with from %100 to 900 px it works.
But I really want this slider to fit in any computer screen. Is it possible to do that?
And can you affect the images to fit into the slider because now i'm seing about %10 of the image.
Or do I have to shrink it in photoshop or something?