If you are editing a map, change some information on the map like the title, then add a marker by pressing the "add marker" button, the changes to the map info will not be saved. This is actually a normal behavior.  That specific page consists of two HTML forms... one for the map info and another for the markers.  Each form have different action attributes and when one is invoked, any changes on the other form will be lost.  The best way to avoid this situation is that after you've made the changes to the map information, press the APPLY button and then add the marker.