Re-install it. BA keeps track of what it has installed and disables those options once installed. To reset the install option requires deleting a registry entry The key is in  HKEY_LOCAL_MACHINE\SOFTWARE\Cakewalk Music Software\Cakewalk\Installers I cannot tell you the exact Melodyne key because I did not install the Melodyne trial.  It should be pretty easy to determine which is the Melodyne key by looking at the data in the records.