The Commentary explains 'ko najja' as 'ko nu ajja'
OYP> ovadito - ???
It's a past (passive) participle of 'ovadati'.
OYP> parimukha.m sati.m upa.t.thapetvaa - to surround oneself with
OYP> watchfulness of mind (see PED under Sati)
I wrote earlier why according to Vibhanga I translate 'parimukha.m' as
'near the mouth'.
I'm sorry that I currently won't participate in this translation any
longer, to be able to direct full attention to other projects. Yong
Peng, please forgive me if I have not fulfilled my promise.