I'm sorry but I can't find the answer in FAQ (it's written to download other maps with Navigator Downloader, but there isn't in my phone!) neither in old forum discussions
Inside App you find on the main menu at the bottom map manager after tapping that on the lefe side map download. You could as well use the Setup utility for your pc and manage download with that software and then synchronize you pc with your phone. Via the windows setup utility you may as well install the pc version of MF navigator so you can plan your navigation on a larger screen of your pc. German version http://navigatorfree.mapfactor.com/de/download/