Old thread, but I'm having the same problem and can't fix it... Even after a factory reset and recovery cache clear and factory data wipe and reset.
I had the plus sign screen show once when I first got the phone, but I vaguely remember dragging it to the trash on accident and it never came back. All the clock does is tilt, but it does not swipe to more widgets.
Alternatively, the lock swipe DOES work for the music and Pandora widgets that show on the stock lock screen. Why does this swipe work and the multiple widgets one doesn't?
I also rooted, unrooted, and after a factory wipe I don't get the normal setup procedures as with a fresh Android. I would hate to lose the stock lock screen as WidgetLocker just used too much battery with this phone... and I really like the full-screen music and Pandora use of the stock lock screen.
Anyone have any ideas?