I just updated the direction of this post: http://www.euroviajar.com/museo-sherlock-holmes-en-londres/
Before doing it I saw again the mappress options and Overwrite existing maps when updating was checked, also I changed the map size from 425×300 to 100%x300.
As you can see the post still have the same width (I also tried the Permanently resize existing maps option and it doesn’t work).
But anyway, what I really want is to have a custom icon depending on the post tags and display post thumbnail, title and excerpt into each POI. How can I do this and update the maps?