Editing built-in sounds for use in ActionScript

First post here - hope I'm putting this in the right place.

I am building a little movie in CS4/Flash (Pro version, student license) for which I want to invoke sounds dynamically from my AS3 code.  I found under Window->Common Libraries->Sounds a collection of sounds that were included with CS4.  Some are amateurish (provided by users?  not clear where they came from), but some of them sound quite usable (and presumably public domain/fair game? again, not made clear).  Only problem is some of them need trimming.  Now I realize you can edit these with Adobe's simple built-in editor IF you plan to simply put them in a frame of the *timeline* for automatic play.  But that edit does not seem to show up as permanent when (after exporting for AS) you play that sound via the SoundChannel class.  I also know you can start playing a sound from a particular point in the mp3 in AS.  But I'd prefer not to determine that point by tedious trial and error for each sound using program statements.  That's what I thought we had sound editors for.

Thus my adventure in madness begins.  Adobe seems to be stymying me at EVERY TURN as I try to edit them.  I am starting to feel persecuted.

My first approach, after copying a sound I liked into my .FLA file's library, was to right click on the sound, and choose "Edit using Soundbooth".  When I do that, I get an error message that says "The file C:........./soundbooth/mp3/The Sound I Chose.mp3 does not exist, unable to launch external editor."  Well, I know darn well that the mp3 file exists *somewhere* on my PC, since I can play it from the Flash built-in library and from my .FLA file library.  But obviously one part of CS4 knows where it is (to play it) while another part of it (the code that exports it to Soundbooth?) does not.  Sounds like a bug, but anyway.

I checked, and Soundbooth itself is installed.  I also chose the standard install when I originally put CS4 on my system.  So I figured, okay, I'll go hunt down the sucker, manually copy it to a folder, and edit it in Soundbooth as if I've never heard of Flash.  I do a search on my entire system, and... the file doesn't seem to exist.  These built-in library .mp3 files must be embedded in the Flash system?  Anyway, the OS has never heard of them.  So...

How can I "export" a built-in sound from CS4/Flash?  I've looked all over the menu system, but it doesn't seem like you can do much with these built in sounds, not unless you like them exactly as they are (or are using the timeline).

PS - By hunting around, I've found that the built-in sounds (for which the path in the sound's Properties window is truncated, abbreviated, elided and otherwise cut off) is actually in a .FLA file called Sounds.FLA deep within the CS4 installation.  That explains why Vista can't find the individual .mp3 files.  Would sure like to know if you can export these sounds though so I can really edit them.

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