Hi Michael,

>That was for English/Number, Kana, and CapsLock keys, is that correct?

Yes.

>The English/Number and Kana keys are modifier/mode type keys is that correct? I mean they don't produce a printable character if you press it just by itself?
Yes, they are special mode keys which used to switch input methods (English <-> Japanese). They don't produce a printable character.
Also I think English/Number and Kana keys are not used for shortcut.
(I add them to the symptom list just to cover all physical key behaviors. I'm sorry if you recognize these keys are modifier key used for shortcut.)

Thanks.

nemuneko