If I knew the entry, I would. Let me look around a bit.
EDIT: Check this and see what it says: HKLM\Software\HTC\Manila there are two keys that have path in the name, one is left, the other is right. Not positive that is the setting for you though as I have TF Detacher installed so I can switch back and forth between TF3d, Mobile Shell 3, and the Today screen.
EDIT 2: Regular today screen, hmm, let me keep looking.
EDIT 3: Not seeing anything else in my registry that jumps out at me. You could check
this out and see if there is anything you think might work. There are a few places there that has stuff dealing with keys. Note, the reg info is the kinda small text underneath each part, you don't have to create a cab file. Hope some of this was helpful...