[SOLVED] Layout - Problem combining fluid resizing with max width

Hi

I'm having a little problem with Atahualpa's Layout settings (under 'LAYOUT style and configure'). I want the layout to resize to suit the user's browser, but I also want to limit resizing to 1280px max, which is the banner width. I think the theme should do this if I set (say) 99% in the 'Layout WIDTH and type' box (first item) and 1280px in the 'Layout MAX width' box (third item). However, this doesn't work for me. The layout resizes, but the max setting is ignored, and on wider monitors the layout extends beyond 1280px.

Could you tell me, please, if am I doing something wrong, or if there could be a conflict with other settings? The max layout width is enforced if I put 1280px in the 'Layout WIDTH and type' box, but then of course there is no resizing.

I'm using Atahualpa 3.7.9 and WordPress 3.4.2, with Chrome and Firefox.

Can anyone help, please? I'd be very grateful.

Thanks!

Kit