i'm guessing you havent replaced either MusicBee.exe or CAD.exe (in the folder CAD is installed, not the MB folder) with the links above
I'm updating both tonight to fix a problem with lyrics but the current links should otherwise work.
With the current versions make sure you start CAD first and then MB
In CAD, if you go to the Options/ About tab does it say 'CD Art Display 3.0 Beta - Build 1059'?
And in the Player Options in CAD does the player location point to MB? you shouldnt need to do that, but it just means MB hasnt registered yet for whatever reason