[wpgeo_mashup] only shows latest post on world map

[Seriousness]

I've been looking around in the boards for some hours now and I cannot find any solution. Hopefully someone could help me out here...

I've created four fresh posts with the wpgeo geodata and used the shortcode [wpgeo_mashup](also in variations with numberposts set "-1" etc) but it will not stop to display only the latest post with a marker on the map. It changes when I put the last one as a draft again or I delete it.

Anybody knows how this could happen? I couldnt find out by looking through the code...

(same question on wordpress.org: https://wordpress.org/support/topic/wpgeo_mashup-only-shows-latest-post-on-world-map)