desperately need help with compile issue

Hi folks,

I have a crazy problem, that has not even been fixed by a clean, start-from-scratch uninstall and install of CS3.  The problem is also occurring in CS4 when I use that on my Intel laptop.

I created a video player long ago that imports and uses the VideoScaleMode and VideoEvent classes.  This .fla compiles just fine in CS3 or CS4.  But somehow now if I try to use those classes in any other .fla, I get a compile error stating the class definitions cannot be found.

As a most basic test, I did the install described above, and then simply created a new AS3 doc and placed this on frame 1:

import fl.video.VideoAlign;

If I then preview the movie, I get a compile error that says the class definition is not found.  If I import the whole package--fl.video.*--it tells me it can't find that package.  But if I open my old .fla right next to the new one I just created, it compiles and works perfectly. 

Can someone PLEASE tell me what in the world could be going on? Particularly crazy is that this suddenly happens in both CS3 and CS4 on two different machines!!  It's like an .fla came down with a case of ignore-the-video-package and then when I opened that .fla on another machine it spread the sickness or something.

I'm totally frustrated and baffled by this.  My classpath settings are identical across all .fla's mentioned. But it can't be chalked up to a file-specific problem, because the issue persists in a brand new doc, created immediately after a total reinstall. 

Could it be that my best attempt at a install from scratch wasn't truly complete, and that the package has been corrupted by a bad .fla and then persisted across the re-install somehow?  This type of thing is the only thing that could possibly make sense to me, but if I didn't get a clean install, then how are you supposed to be able to do so????  I can't even find the class manually to point a classpath to it, as it must be one of those AS3 packages that is pre-compiled into the player or something...

Any help is GREATLY appreciated...