Conflict with maximenu CK

For some reason, getting an odd error if I try to use maximenuCK with my template:

www.templates.guildsite.info

If you click on the maximenu link, then it is Maximenu used.
If you start scrolling, then the menu jumps to top left on the screen.
This doesnt happen with the other menu items (they are using a different menu creator)

Hi
in the effect options >> deactivate the "top fixed" position
CEd