Can anyone help? Tractor and iTunes issue.

I'm having trouble with Traktor SP playing anything from my iTunes library via the node in traktor.

I have recently reinstalled everything on my Mac and its running 10.11.6.

The music is stored on an external HDD and I have pointed Traktor at the iTunes library XML file that is on this drive - it must be the right one as iTunes doesn't have an issue with it.

All of my tracks are greyed out and I cannot load ANYTHING. I'm getting the message that files are missing, corrupt or unsupported.

I have tried to relocate several of these manually using the menus in Traktor, but when even when I do this, the tracks are greyed out in finder and I cannot update them.

I have a gig tomorrow night, can anyone help?!