If you've got the same problem, then it's because you're trying to download that link on your desktop. That link is meant to be opened on your blackberry and run from it's browser. It will download the application OTA and load it without the need for desktop manager.
Also, if you had the bes version, did you do a "Switch Device" at all from a previous device that had it? If so, you may have a copy in your temp folder already.
Need to search for a folder with the same name as your BB's pin.
The version I posted should work with a BES environment unless they have your data on the carrier side restricted with an IT policy.