The glitch with the Japanese Kotoeri IM reported here has been fixed in the OS 10.9.1 update released 12/17/2013. Kotoeri Preferences (found when one of the Japanese IM's is selected in system preferences/keyboard/input sources) now has a setting for the keyboard layout, as was present in 10.8 and earlier.
Apple has also issued a note regarding a problem some users have encountered with a grayed-out Hiragana input.
In case you are wondering where the "Register Words" option for Kotoeri has gone, this function has now been taken over by system preferences/keyboard/text/text substitutions, as explained here.
Apple has also issued a note regarding a problem some users have encountered with a grayed-out Hiragana input.
In case you are wondering where the "Register Words" option for Kotoeri has gone, this function has now been taken over by system preferences/keyboard/text/text substitutions, as explained here.