In flex 4.0/4.1, there is always the application preloader. (swf download progress bar) I just upgraded to flex 4.5 SDK, and I immidiately noticed that the preloader is gone. Anyone noticed that? I double checked by going back to 4.0 again, and confirmed that it showed up in 4.0 and 4.1, but not in 4.5.
I tested more and found that if I do:
preloader="mx.preloaders.SparkDownloadProgressBar"
the loading bar will NOT show up.
If I do
preloader="mx.preloaders.DownloadProgressBar"
the loading bar will show up.