I have created a banner ad, which when i test the movie in flash it works perfectly, but then when i go to export it to a .swf file, it only plays the first scene.

I debugged the movie and it came back with this result:

Attempting to launch and connect to Player using URL /Volumes/HD-PCU2/Work/Multimedia Develpment/MainProject.swf
[SWF] Volumes:HD-PCU2:Work:Multimedia Develpment:MainProject.swf - 15467468 bytes after decompression
Error: Error #2067: The ExternalInterface is not available in this container. ExternalInterface requires Internet Explorer ActiveX, Firefox, Mozilla 1.7.5 and greater, or other browsers that support NPRuntime.
at Error$/throwError()
at flash.external::ExternalInterface$/call()
at MainProject_fla::MainTimeline/clickExpand()[MainProject_fla.MainTimeline::frame1:8]
Cannot display source code at this location.

I am struggling to understand this code,

Would love some help,