[Plugin: Geotag] accessing post markers

Thanks for a good plugin. I have a project that needs geotagging of posts and a map showing them all, and I’m surprised by the lack of up-to-date WP plugins doing this. However, even though this is marked as only tested up to 2.7.1, rudimentary testing is going OK on 2.9.2.

My question here is about showing a map with all tagged posts, e.g.:

[gmap marker_query="numberposts=-1"]

I want to be able to list the post titles / extracts next to the map, with a GMap marker next to each post that matches its marker on the map. Is there a way to give the map markers for each post a sequential letter, like on the GMaps Local Business search?

https://www.ads-software.com/extend/plugins/geotag/