There are some strange problems when i used swc files in my as3 project

Question

Hello everyone,
        My development environment:  fdk4.0,  flash cs5.5,  I publish fla file by using flash cs5.5,   publish setting is  fp version :10.0&10.1 ->swc. I imported swc files to my as3 project and  complied them by using flex sdk4.0. When i run my project,fp was crash.   when i republished on fp 10.2, the project works. Is there any reason?
        another strange problem, for example   a MovieClip's aslink named "A" in swc, it has a textfield named "subText".  I write code like below:
                        var mc:A = new A();
                        mc.subText.text = "test";  
         when mc called "subText" , fp throws null property error, it can't find  subText..  very small number of movieclips have this problem,  I sloved this by duplicating a new one and rename it.
         but i don't  know why ? 
          thank you for your reply.

Answer 1

I should have figured that out from your original post. I think there is a possibility that your bookmarks/history database (places.sqlite) has a corrupted record. Rather than take drastic action on that immediately, could you do a test? The test is to exit Firefox, rename your existing database, and restart Firefox. Firefox should import your last bookmarks backup. You then could check whether the problem remains or whether you got a clean restore of bookmarks. After the test, assuming you prefer to retain your history, you could undo the procedure and try restoring your bookmark backup into the database to see whether that overwrites the problem record. If not, then we would go back to possible drastic action.
'''Test procedure''':
Open your current Firefox settings (AKA Firefox profile) folder using
Help > Troubleshooting Information > "Show Folder" button
Switch back to Firefox and Exit
Pause while Firefox finishes its cleanup, then rename '''places.sqlite''' to something like places_20130614.sqlite. Keep this window open.
Restart Firefox. By design, Firefox should import your last automatic bookmark backup.
If you return to the Library dialog, how does it look?
'''To reverse the test''' (but preserve a backup of your history/bookmark database):
Exit Firefox
Delete the newly created places.sqlite file
Right-click copy and paste the places_20130614.sqlite and rename the copy to places.sqlite
Restart Firefox and open the Library dialog. Should look like it did a few minutes ago before any changes.
''If the test showed no corruption,'' try to restore your last bookmarks backup. The procedure is described in this article: [[Restore bookmarks from backup or move them to another computer]].
Does any of that get us closer to a solution?