Вам необходимо отредактировать как ресурсы изображения, так и файл .css, ниже приведена часть CSS, которую вы будете редактировать.
//---------------------------------------------//
.jslider .jslider-pointer {
width: 13px;//<-- increase the width here to match your new image...
height: 15px;//<-- increase the height here to match your new image...
background-position: 0 -40px; // you'll be editing this here as well based on what changes you make to the image, which is a imagemap of multiple different distinct image elements in jslider. any changes here need to be applied throughout to other elements
position: absolute;
left: 20%;
top: -4px;
margin-left: -6px;
cursor: pointer;
cursor: hand;
}
//---------------------------------------------//
.jslider .jslider-bg i, .jslider .jslider-pointer {
background: url(../img/jslider.png) no-repeat 0 0;//<-- edit this image to the dimensions you need
}
//---------------------------------------------//