Custom query maps with custom taxonomies & custom post types

I created a directory of cultural actors of my region using CustomPress and I've integrated it with Google Maps plugin as well, but I'm stuck at this point:

I want to show common maps on top of the listings of my custom taxonomy archive pages. I'd like these maps to show only items from the custom post type I created that share the custom taxonomy of a certain region, but I tried digging deeper into the capabilities of the "query" parameter of the shortcode and couldn't find the answer, how would you deal with that?

Also, as a side-question if you could... I currently allow users to create posts of this custom post type using Gravity Forms + CPT addon but I'm having trouble afterwards for letting the users edit the content and custom fields, taxonomies etc... of their posts on the front-end after creating them. Any ideas or plugins from your collection that could help me achieve this?

Thanks for your attention and support