I have a Flash map that was developed by an outside vendor in 2010. I have made modifications to the text strings in the associated .as files since then and have had no trouble with the resulting exported swf. I believe these were made before updating from Flash CS5 to Flash CS6.
Yesterday I made one small correction in a text string and exported a new SWF. The new SWF is proceeded by a preloader. The preloader runs and the progress bar goes to the 95% mark and then hangs in IE 8. It runs fine in Firefox 20.0. I have exported the SWF using Flash CS5 and Flash CS6. The results are the same.
Any help you can give would be greatly appreciated!
We'd need more information on what you changed to comment. Could it possibly involve a string delimited by apostrophes and you added an apostrophe in the middle?
var myString:String = 'This string doesn't terminate correctly.'; // error, the apostrophe in doesn't causes an error
This would cause a syntax error before compiling the SWF, but the idea is the same with any externally loaded text, such as XML. Characters thrown in can cause issues if they're not encoded correctly. Don't consider this example too literal considering the compiler would catch it.
If something simple like that is not the case you'll have to share the code so we can spot errors.