New Mac, iTunes Lib missing in Rekordbox, .xml is checked

Hey Guys.

First of all i dont use itunes for my Music Collection.

So, i do not have much to do with iTunes.

A good buddy from me getting a new Mac Pro.

Rekordbox is new installed. 

- We copied all the Tracks to an external HDD.

- Then we copied all Tracks to the new Mac.

- We imported all Tracks to the Lib. from Rekordbox.

Then, he told me, that he is using the iTunes Library for sorting his Music.

We managed to import the playlists from iTunes.

So, now we see all the Playlists from his iTunes Lib.

But there a no Tracks in it. Same in iTunes. We see the Playlists but there are no Tracks.

What we have to do?

Is it possible to "refresh" the iTunes Lib., so that the Playlists in Rekordbox and iTunes update automatically?

Few minutes ago he wrote me a message that he cant copy his iTunes Lib. to an external HDD. Permission denied or something like that.

Thanks in advanced...

René (Wenn möglich auch in deutsch antworten =)