Hi, thanks very much for the Sparkling theme. I have the homepage slider set up on my site ironbutterflydesign.co.uk and it is displaying as I want. Images size I am using is 1920 x 550 to achieve the same look as the Sparkling demo.
I have tried testing it on my tablet using Safari and its not displaying as the desktop. The images do not reach each side of the slider and also slider box (don’t know technical term) is a much narrower in relation to other elements on the page.