Couloir Slideshow no longer relies on the prototype/scriptaculous libraries and has been fully recoded to support jQuery which is included with Drupal 6.
This change fixes many long-standing conflicts with other modules, particularly Lightbox2.
Starting with Couloir Slideshow 6.x-1.4, it is actually required that Lightbox2 be installed and enabled for any Lightbox effects to occur with the slideshow. It is not a requirement of the module to have Lightbox2 installed, however, if Lightbox2 is not installed, clicking on an image will open the corresponding image itself.