Manulla is the name for the civil parish. The Catholic parish name is Balla, and you can find the parish records for Balla online at this link (marriages going back to 1821, wth some gaps early on, and baptisms going back to 1837): https://registers.nli.ie/parishes/1044
You can find more info about Cregg at this link: https://www.townlands.ie/mayo/carra/manulla/balla/cregg/
My grandmother was a McNulty from that part of Mayo, so I can add some info about the family, in case you're interested. In Irish, the surname McNulty is Mac an Ultaigh, which literally means “son of the Ulsterman”, but may simply refer to descent from the Ulaid, a people for whom Ulster is named (in ancient Ireland, the Uluti tribe), which in remote times ruled the entirety of the North of Ireland. According to MacLysaght’s “Surnames of Ireland”, the McNulty surname originated in County Donegal, and that is where the Mayo McNulty’s came from. A family of McNulty's migrated to the Callow Lakes area in eastern Mayo in the 1640's, according to a history of the parish of Killasser. In the course of time, McNulty’s became numerous in the region. There are also still many McNulty’s in Donegal and nearby counties. McNulty emigrants from Ulster are also known to have moved to Counties Louth and Meath (in Meath, they usually just use the name Nulty)
