Again, the theme width is 1140px not 960px, so you would have to add an 1140px width image. The slider images don’t center (that’s just the way SP designed it), so you have to make the images stretch the width of the theme in order for it to “appear” centered.
Also, you need to have more than one image in order for the pagination (little circles) and the shadow to appear correctly with this particular slider. If you just have one image, then that sort of defeats the purpose of a “slider”. For one image you’d be better off just adding the image directly in a text widget instead of using a slider to show this. Removing the slider will save you some load time. If you do plan to have multiple images, then add more in the settings so everything will show up properly. Let me know once you do either of the suggestions to make sure its working properly.
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