Solved.
I managed it the following way:
Change in the templates index.php the following line
<?php } else if ($menu->getActive() != $menu->getDefault() { ?>
to
<?php } else if ($menu->getActive() != $menu->getDefault() && !$this->countModules('slideshow')) { ?>
By the way I thought that the following lines are a bit overkill:
if(jQuery('.cholder-inner').height() < jQuery('.rotate').width()) {
jQuery('.cholder-inner').height(jQuery('.rotate').width()+220);
}
I removed the +220 at the end. If this isn't a good practice for the sake of for me unknown circumstances, please don't hesitate to tell.