Content Width override

Hi all,
I have a Joomla install of Gk Fashion and am trying to implement an override rule for the mainbody width of a particular K2 item.

I have entered the K2's ItemID's in the 'Content Width' area of the Layout section and and give the value of 4. With column wight set at 220 I would expect the mainbody with of this K2 item to be 880 pixels but am still getting general mainbody width of 2 x 220 pixels.

I have checked all obvious problems but no joy. Am I missing something in documentation http://www.gavick.com/documentation/joomla-templates/templates-for-joomla-1-6/gavern-3-0/responsive-layout/ such as format for entering item Id or other.
Any ideas or solution would be much appreciated.
Thanks
Paul

Hi,
can you send me PM with access to your joomla backend ?