Flash Builder 4.7 SWC contents garbled, works in FlashDevelop

Question

I have an all-defaults Action Script - Desktop (Runs in Adobe AIR) project with a single MovieClip on the stage from a SWC file created in newest Flash Pro CC. The MovieClip contains buttons, text, etc, for a menu system.
When I build and run it in my regular IDE (Flash Develop), it looks correct:
http://snag.gy/7UFFN.jpg
When I build and run in Flash Builder, it is a complete mess:
http://snag.gy/7Er2e.jpg
The problem is more than visual; DisplayObjects within GfxMainMenu have been randomly swapped with others from the same SWC. When I try to hook up my buttons, I find some of them are actually missing. The weird upside-down ghost logo MovieClip has actually replaced the orange SimpleButton. Needless to say this makes profiling difficult. I've been having this problem with Flash Builder for 3 years across many versions of FB, AIR, Windows, etc etc. Every year I try again with a new approach, hopeful that they've fixed this and I might be able to use FB's excellent profiler for this project. But the basic issue is the same: FB hates the contents of this SWC and I can't find a way to cleanse the demons from it.
This is the code:
public function Main():void
  addChild(new GfxMainMenu());
You can download the project and SWC here - I'd love to know if others can at least recreate this:
https://dl.dropboxusercontent.com/u/11786661/FlashBuilderTest.zip
Anybody have any clues?

Answer 1

Looking into this further, all the garbled symbols appear to be SimpleButtons. Their up, over, and down states are either blank, or they contain random symbols from elsewhere in the file. Many of my buttons contain dynamic TextFields with embedded fonts... but I think the problem may occur in a situation as simple as having 1 shape-filled button and 2 exported symbols in the same swc. I've been taking things out of the swc or copying them to a fresh fla all morning trying to track down a specific simple example of the bug.
But it's gotten hard as FB started crashing and nuking my workspace repeatedly. I remember how much I hate this thing now. FlashDevelop has a great editor and debugger, and Scout is a good profiler, but there are things that only FB can do. Specifically, tell me which references are preventing my objects from being garbage collected.