I don't know if it is still this way or not, but RIM used to provide versions of desktop manager with and without media manager. If you don't see the module in your version, then you'll need to download the version will. But you may not need it.
You can simply set your blackberry options to enable mass storage mode, and you media card will appear as a drive when you connect to the computer. And then you can drag and drop file as you wish. I advise trying that first. Many people find media manager to be very buggy. If you don't need it you may want to avoid it.