I'm trying to move a referenced iPhoto Library to an external drive.
You can't unless you can Hack SQLite or upgrade to the latest version of the OS and iPhoto and purchase Aperture - one (of the many) reasons that a referenced library is strongly not recommended is that there is no suppoted way to change the path to the referenced library
Has anyone tried restoring a referenced iPhoto Library form a Time Machine backup?
Will it keep the references and description info?
That is not a problem as long as the path to the referenced photos has not changed - it it has then you can not - see above
For more information on the many reasons NOT to have a referenced library see the User tip on iPhoto and file management