When you set a department (or content page) to 'Show Banner Ads' the software is looking for the code for that particular BannerGate ad or BannerGate ad category to show.
To get your BannerGate ads to show, you must add your BannerGate cf tags to the fields in within your site's Control Panel
Under Master Settings ---> choose 'Edit Site Descriptions' ---> and look for these four fields: 'Top Page Public Banner Ad Script' - 'Top Page Member Banner Ad Script' - ' Bottom Page Public Banner Ad Script' - 'Bottom Page Member Banner Ad Script'
Add your BannerGate cf tags to whichever of the four fields you wish for the ads to show on your site on pages you have specified to allow banner ads to appear.
Now, whenever you set a department page or a content page to show the top and bottom ads, the ads in the bannergate code will automatically show on the top and/or bottom of the page.
Content page setting field is titled: "Show Banner Ads within Content"
Department page setting field is titled: "Show Banner Ads on Page?"
Within your content and department page fields you have four different options to either show no ads, to show ads just on the top of the page, to show ads just on the bottom of the page, or to show ads on both the top and bottom of the page.