Nero, latest version??

I now have this program on trial and wanted to know if it can playback. I have copied cd's and dvd's on my new external burner for my notebook and can't playback anything.

I have burned on my cd/rw burner on my notebook and played back the cd with Windowns Media Player and then also played back dvd's with the Intervideo Win DVD.

If I can do this and my external burner is connected by a usb 2.0 does anyone know why i can't playback on the external burner?
I can't see where there is an option though;on the Windows media player to change the source to have the external burner play? Or will this program work with the burner, I believe it should.

And then I get back to ...can Nero playback??

I tried Roxio and it could playback, however it was not good for copying cd's and thus I am trying out Nero.

Appreciate all comments, thankyou