I posted an abbreviated version of the Locked Room Lecture a while back.
http://forums.animesuki.com/showthre...42#post2797842
I don't think Ryu is anywhere near Carr as far as locked rooms go; too many of the mysteries is Umineko are based on the absence of duplicate keys. (On the other hand, this is likely deliberate; as Wright mentioned, solving one Carr-quality mystery would likely tie down a good deal of Umineko.)