We think it's something to do with the script not getting the 'upload_id'. That's what Ania's looking into now.
If you try to run the .pl file from a browser you get this:
Failed to make /home/designisdark/darkaudio.co.uk/temp/.dir: No such file or directory
Before .dir there should be the upload ID...
We deleted the incorrectly named folder and then got this error, also worth putting in the post:
Failed to open .link: Inappropriate ioctl for device