css styling subpages

Greetings,
I wish to display a unique banner on individual subpages. I've followed instructions in this forum, but must be doing something wrong.

Here's what I've done:
1. Created Menu item pointing to K2 item - added Page class suffix .mfc
2. Added #gkHeader .mfc to override.css and included my css stylings.
3. Created a custom html module and assigned it to the header position and added .mfc to the module class suffix.

I just can't seem to get any stylings applied to the header module position on subpages... See results here:

http://www.3rdglance.com/bu31/index.php/store-item

Look for 'stuff' just below breadcrumb module.

Wouldn't it be easier to create custom HTML module and select on which pages it should appear? This way You can create as many modules as You need, all in same position, just displayed on different subpages.

Yes, and this is what I'd like to do, but I find that the only way I can make module stylings display is if I put the css in the Custom CSS field of the Template (in Extensions -> Template Manager -> Creativity Subpages). If I place the same CSS in override.css, stylings do not display. Why is this??

I dont see override.css loading at all. Have You enabled it?