Hello
There is no real solution to your issue as your slideshow is set to 100% width. To display all of your image the slideshow needs the same ratio set as the images used. As your slideshow is set to 100% width this will be forever changing as it will vary depending the screen size it is been viewed on.
You could trick around with forcing the width of your slideshow with something like the following, editing to your own taste...
.slideshowcontainer {
max-width: 1400px;
}
CiarĂ¡n