Music previews

[uncletadd]

I hve managed to set up music downloads successfully. Now having problems configuring the Previews that a customer can play before buying. I went into Media Manager, then created a collection, Clicked on edit then tried to add a clip. It seems as though the clip is loading to the main directory. the progress bar reaches the end but the collection does not show thata clip has been link to the collection. When I click on Assign a product this seems to complete successfully and it shows on product assigned. Unfortunately the clip is not showing on the customer side.I am on a windows server using the ZC 1.3

Any help will do

Thanks in advance

[uncletadd]

Guys I am Still stuck. Any little help will do.
Thanks in advance

[jahype]

have you set up the .mp3 extension in the 'media types' of the same media manager pull down?