The steps I underwent:
I had installed Flex Builder 3 beta 2 (FB 3 beta 2) as a plugin on my Eclipse 3.2
Opened my Flex SWF Library projects inside of Flex Builder 3 beta 2
Selected Flex 3 M3 (Beta 2) SDK at the dialog (default value)
Flex Buidler 2 had given me [...]
Mine Flex 2 authored SWF is 19 levels deep in its full glory:
_level0.index0.VBox5.GradientBox25.indexViewStack.
mainPage.contentPane.mainViewStack.customerViewStack.
presentationViewer.swf.FlexLoader396.instance458.sfiViewer.
bank.foreground.sa04d14eaa39b3fd.content.clip
