Well, it took me a couple of days but i finally manage to understand most of the song. 
I warn you, i understand neapolitan quite well but i'm not from campania so I didn't get a couple of phrases and i don't know if the spelling is correct....anyway this is the best i could do, here you are:
Quann o sole è doce e te miett 'n cammino/ when the sun is sweet and you set off
fermate nu poco pe sentì a voce / stop for a little to hear the voice
della chiara funtana/ of the clear fountain
comm a na preghiera quest'acqua fresca/ like a prayer this fresh water
ca ta fa felice fin a quanno è sera/ that makes you happy till night
fattela bastare/ make it be enough
Cunusciuta e avuta a terra ??? di giuda
cresce la salvezza e nun me fa campà/ the salvation is growing and it doesn't let me live
vola vola l'ammore a portare nu sciore e poi torna da me/ flies flies the love, brings a flower then comes back to me
Sul' per chi resta sta fatica è amara/ only for those who remain the fatigue is bitter
ma nun ce pensate che riman' è festa/ but don't think about it, tomorrow it's a feast day
festa da maronna/ holy mary's feast
festa du paese e da maronna nera/ the feast of the village of the black holy mary
perchè è riturnata solo pe stu mese/ because she has returned only for this month
da na terra luntan/ from a faraway land
cumm è longa a via pe' turnà a casa mia/ the road that takes me home is so long
stelle dellu ciel m'aite accumpagnà/ heavenly stars you have to accompany me
cumm è bell' o culure o...???
quann o sole è doce e te miett 'n cammino/ when the sun is sweet and you set off
fermate nu poco pe' sentì la voce/ stop a little to hear the voice
della chiara funtana/ of the clear fountain
ma nun ce penzà, ma nun ce penzare/ but don't think about it
ca rimani è festa, festa du paese e da madonna nera/ that tomorrow is a feast day, feast of the village of the black holy mary
perchè è riturnata sul pe stu mese/ because she has returned only for this month
ma nun ce penzare ca rimani è festa/ but don't think about it
sul per chi resta sta fatica è amara / only for those who remain the fatigue is bitter
ma nun ce penzare, ma nun ce penzà/ but don't think about it
"-Please tell me you're going to appeal to my humanity..."
"-Actually, I'm planning to threaten you."
"Well, if you'll excuse me, I have work to do. Evil plots don't just make themselves, you know!"