Hi Spencerbutler,
Welcome to the forums!
What version of NED are you running? In fact what version of OSX are you running too? (e.g. 10.4.x, 10.5.x, etc)
Have you got the latest version of Quicktime installed?
If you are running OS 10.5.x and have downloaded the latest version of NED (NED 3.1) have you referred to the videos on how to use NED?
http://www.macprovideo.com/support/
It's really important that you log in to NED using the same username and password you used when purchasing tutorials.
Thanks
Rounik