Sorry, really sorry!
I make a mistake: I tested with wxLaunchDefaultBrowser, not wxLaunchDefaultApplication.
wxLaunchDefaultApplication( project_dir ) works fine on Windows.
I just did not know wxLaunchDefaultApplication().
Sorry, really sorry!
I make a mistake: I tested with wxLaunchDefault Browser, not wxLaunchDefault Application.
wxLaunchDefault Application( project_dir ) works fine on Windows.
I just did not know wxLaunchDefault Application( ).