Re: 14-42 lens lock issue
Its nothing to worry about as the lock is just to fold the lens for storage to make it more compact and take less space in your camera bag or pocket. You could say its a modern version of the old cameras with bellows that used to fold away for storage.
I don`t know what other M4/3 lenses have the same lock if any.
Of course there are other lenses from Olympus and Panasonic so if you don`t like the way the Oly 14-42 works there are alternatives.