Custom Maps don't show detail after Basecamp Update

I recently "updated" my basecamp software and now the kmz maps I created in Global Mapper have lost all of their resolution - I have created new maps - same problem. All the detail was lost - the map is there, but you can't zoom in any make out any of the terrain features - just blurry larger pixels. I have "map detail" set to "Highest" and "profile" set to "Walking." Thanks in advance for any help.