To be honest, at this stage, I am struggling to come up with any more specific County Down words, it is a (presently) extinct dialect at the end of the day, unfortunately.
However, here are a few words of County Down Irish which can be found in Oriel Irish in general and in East Ulster in general.
Práinn = haste
Is mór an phráinn seo ort = you are in a great hurry.
Déan práinn = hurry up.
Feidhm = need
Má tá feidhm airgid ort = if you need the morning
Cosúil = reasonably
Tuigim go cosúil é = I understand it pretty well
Alt = a glen
cuiseog = 'a wind straw'
aidigh = admit
áite = a place (<áit)
dadamh = anything
coitcheannacht = community