When put a block containing Couloir Slideshow, the DHTML menus don’t work ok.
Details:
Without Couloir Slideshow block: if you click on a parent menu with submenus, the parent menu is expanding / contracting. In order to see the associated node to the parent menu you must double click this menu.
With Couloir Slideshow block: if you click on a parent menu with submenus, the parent menu is not expanding and the associated node to the parent menu is shown.

You can test it here for the moment. The Colouir Slideshow block is set to appear only on the front page.