Hello,
You are correct that the pages created by GD are not accessible as ‘pages’ as they are created from templates in the plugin, and those are specifically post archive ‘type’ pages.
If I understand you correctly you would like to have some kind of custom layout for each of the archive pages for each of your CPTs: events, and venues.
These are the steps that would be taken to create a page like ‘our-venues’
Create page, set slug to ‘our-venues’
Add shortcode for Listing Map
Add shortcode for GD Listing shortcode – set post_type to gd_venue
Done
Add additional GD Listing shortcodes as needed to sort/sift/filter your listings as needed.
The map will only show the listings that are on the page.
You can create your own custom CSS to hide other aspects of the map as needed.
Let us know how it goes