The complete re-install went just fine, the TV function works perfectly. I still can't connect to my media files here. I had a look with putty and the paths needed to this pc aren't there. I'll make a copy of one of sources.xml file that should work and try that.
Edit - I found out why I can't read files from a USB stick. It's because I put the stick into the USB slot in the front of the box, it needs to go in the rear. I found that on some site, anyway that works now.