Transparent Background for Flex App

[BruceND75]

I am using a Flex 'spinner' component to create a SWF I can use while waiting for an operation to finish. I would like the background of the Flex app to be transparent, so it will play equally well whether the underlying screen is white or black while the user is waiting.

Is there a way to make the background of the Flex SWF transparent?

Please note: I am Not talking about making the SWF transparent above HTML. This will be a SWF that will play within a larger AS3 Flex app.

Thanks in advance for all help.