Thanks Flandry, nice script!
Some problems:

• the .navit folder has to be under /home/user and not /home/user/MyDocs
• the name of the map has to be mymap.bin and not mymap.dat
• the download of the navit-xml.tar.gz file in the script doesn't work for me (I used the browser to download it)

To create a route just search for a location and set it as destination.