My Mooshimeter was hold at the customs in Dortmund. They just wanted a copy of the eMail I got from Dragon Innovation. The guy at the office was really nice and allowed me to forward the mail to him from my smartphone and he printed it for me.
They said nothing about any conformity stuff like that.
Had to pay the import taxes (“Einfuhrumsatzsteuer”, 19%) and got the meter without a problem after that.