Locking & Unlocking buttons?


So I know of two ways to lock the buttons:

1. Under system settings->Auto-lock (during activity, etc) I have it still set to Off.

2. CTRL->Lock Keys.

However, I've been hesitant to try these because I've been unable to find information on how to unlock the buttons.

So...how do I do that?

And is every button locked when that's on? ie: I have no ability to manually set a lap if things are locked, right?