Download not working (no error)

Hi there, I am using download monitor for many year together with email before download. Email before download works fine but once the download link is shown, you can click on it and it looks like the website is doing something but its and endless loop and the document is not downloaded. If i just use the download link directly as URL the following message appears: Invalid UID Please fill out a new form to generate a new link.

The page I need help with: [log in to see the link]