I wondered why the "Add Map Box" item is not active in the "Modern Lines" theme (among others). After searching the forum for that topic I came across these two posts [http://discussions.apple.com/thread.jspa?messageID=12351013�] and [http://discussions.apple.com/thread.jspa?messageID=11807308�], which are unfortunately archived. As I needed a solution I started digging in the plist files as recommended in one of the posts above. The "Add Map Box" menu item is active in the "Photo Journal" and "Photo Essay" themes. After comparing the files Theme.plist in /Applications/Aperture.app/Contents/Resources/Book Themes/Modern Lines/ExtraLarge and /Applications/Aperture.app/Contents/Resources/Book Themes/Photo Essay/ExtraLarge I found that adding the two lines <key>defaultMapStyle</key> <string>PhotoJournal</string> also for the "Modern Lines" Theme.plist I was able to add map boxes.