I am posting this in the hope that it might help others out there avoid wasting hours on debugging an issue which I came across today. I duplicated two existing maps on a separate sheet in my app and referenced these in my mashup. However, I could only get one set of maps to display, depending on which tab in my mashup I visited first.
It turns out that when you duplicate a GeoAnalytics map on a separate sheet, it keeps the internal GeoAnalytics ID and it seems that this needs to be unique within the mashup. After re-duplicating these maps on the same sheet, I could see that the internal GeoAnalytics IDs were different, so I deleted the original duplicates. I then changed the object IDs within my code and, hey presto! , all four maps were displayed, independent of the order in which I opened the mashup tabs.
I hope this helps.