Hi, I have tried to install Norwegian language files for Appointment+, but seems to have failed with this. I have exported the language files in both .po and .mo format and uploaded them to both the both the global and the plugin language directory.
EDIT: I also have problems adding the WPMU Dashboard to my subsite. However, I guess you can access web.agog.no/advokat from the main site http://www.agog.no
Good luck! Please also let me know what I did wrong, for future reference.