sfx flavor = WindowsForms & Quiet does not exit without user interaction


I'm creating a sfx that runs Setup.exe. The sfx Flavor = WindowsFormsApplication, Quiet = true. According to the documentation for PostExtractCommandLineProperty,

"If you set Flavor to SelfExtractorFlavor.WinFormsApplication, and set Quiet to true, then a GUI with progressbars is displayed, but it is "non-interactive" - it accepts no input from the user. Instead the SFX just automatically unpacks and exits. "

The behavior that I observe is that the sfx does the extraction with a small dialog showing extraction progress, launches setup.exe, but instead of exiting, displays a Quit button on the dialog.