I don't know how many of you undestood that, but if you want to move a centered menu some pixels to the right or left you CAN do that using the left attribute...
the only problem is that you have to substitute the numerical notation with this
'offset=xx' where xx is the number of pixels you want to move your menu.
I didn't see this written anywhere... the faq tells you to put in a simple numerical value as you would do for a non centered menu, but this doesn't work.
Cya!