Hi,
The mashup doesn’t really center on a particular POI. It adjusts its center and zoom to show all of the POIs. You can use the “initialopeninfo” parameter to open the first POI in the mashup.
If you are using the latest beta (http://mappresspro.com/betas ) the “first” POI is the one that is alphabetically lowest (POIs are sorted alphabetically by title), for example “aaa”.
To apply a different sort order there are two options:
1. The easiest way is to just turn off the default sorting using the mashup parameter sort="false". Then you can set a POI order in your query using the clause ‘orderby’:
show_query="post_type=post&orderby=author"
2. If you know some PHP, there is an action mappress_sort_pois you can use to sort the map POIs.
You would need to implement that action in your functions.php file. You can see the default implementation in file mappress_map.php as an example.