Hello,
An “Archive” is a WordPress technical term for a page where all of the past posts of a particular post type are displayed. That is called a Post Type Archive. Then there is more than one type of archive, as there can also be Post Type Category archive and post type tag archive.
When the Archive template is edited, that will control the output on a page like /places/ (post archive) or /places/category/my-category/ (post type category archive).
When a post is view on the archive, the post is shown in a small/mini format. This mini format is referred to as the ‘archive item’ meaning, it is the way the listing/post is shown as an ‘item’ within the archive page itself.
So, there is the archive-item template, which controls that output. Then there is the GD Details template, which is the full page view of a post.
To see which templates you have set and where to edit them, visit
GeoDirectory – Settings – Pages
On that page you can click to edit the archive, archive item, or details templates.
The Design page settings are for the edge case for certain themes. Best to set that for auto unless you need it.