Yes. rekordbox 5 follows all the functions of rekordbox 4.
rekordbox can be installed to any number of PCs/Macs free of charge.
A license key may be required depending on how it is used, and which model you are using.
*This is a single application. There is no separate free version/paid version.
You cannot load Track Libraries from applications other than iTunes directly, but you can load Playlists, Cues, and beats and tempo information from other applications if you convert them to rekordbox.xml format first. For details on rekordbox.xml format, click [here] (http://rekordbox.com/en/support/developer.php "").