I got a reply from kelly.li@geniatech.com this morning. She confirmed that she resetted my activation key. 🙂👏
Therefore, if you need help, Kelly should be the correct address.
FYI: Additionally to the reset by Kelly, you have to delete the plist file com.elgato.eyetv.plist from Users:Shared:Library:Preferences
The invalidated activation code information is saved in this particular file and will be used by the app at every start up.
Best Regards
Thomas