is there a way to have Flash import an flv video so that portion of the video has an alpha channel, therefore the contents from the flash movie underneath of the video shows? Can flvs support alpha regions?
No, you'll have to prepare the video in another application e.g such as after effects, with the necessary area in the alpha channel masked, then export as an .avi or quicktime(animation codec) that supports an alpha channel before importing.
well here's the thing,
Flash has the option to disregard the stage color and create alpha channel in place on export (which is all I need) ...as I understand that, that should give me transparency in the mov file I'm exporting wherever stage is visible.
thing is i don't know how to test the mov whether the alpha is actually there. That would be a wise thing to do before I continue to making the flv from it