Languages: english and german.
This module exists in different releases for Joomla 1.5, 2.5 and Joomla 3.1. So make sure that you download the correctly version for your Joomla.
Before anyone complains about sh404sef problems, where the categories work fine, insofar as SEF urls are concerned, but the details pages do not work, make sure you download the latest fix for your sh404sef plugin. I updated to the latest version of jdownload, which is 1.8.1 at this point, but did not update the plugin. This was my fault. So, the urls going to specific download details used to be in the form of: mysite/view.download, but the updated sh404sef plugin file corrects this. If you see this problem in your installation, get the fix and it will be fine!
Please everyone, take the time to research things before giving a bad review to others. The true problem might be yours, as it was in this case, not the extension!