You can load tracks from an audio CD and they will be cached automatically in Zulu. The cached tracks can be played without the original Audio CD.

To load an audio CD into Zulu, click the "File menu and select Load Audio CD". If your audio CD is in your CD drive, the tracks will appear in a list on the Load Audio CD Track(s) dialog. Select the tracks you want to load into Zulu by pressing Ctrl while clicking select tracks, or press Shift while clicking to select adjacent tracks. Click the Load button to load the selected tracks into Zulu's Music List, and into Zulu's cache.

You can delete the cache tracks from the Options dialog on the General tab by clicking Clear Cache. Once you have deleted a cached track, you will be unable to play it in Zulu unless you load it back in again.