If you had a previous version of MediaMonkey Gold installed, and
deleted it prior to installing the new version of MediaMonkey, then the
configuration settings of your Virtual CD will be lost, and any tracks
previously saved to the virtual CD will be greyed out when attempting
to play them.
To fix this, go to: Tools | Options | Virtual CD & Preview, and set the
Virtual CD directory to the location where Virtual CD tracks had
previously been saved.
Note that the Virtual CD feature is intended to cache library Tracks that are
inaccessible (e.g. from a CD/NAS) to the local hard drive. Thus you cannot
add the VirtualCD folder to library OR assign a folder from the library to act
as a VirtualCD folder.