On further inspection, I think the boundaries are correct here. EDs and registrar districts do not follow parish boundaries. For "Bullaun Registrars District", the two areas touching at a single point do seem to be correct. The parish boundaries run along the quarry and the EDs and registrar districts run along the road.

Useful link:
https://www.dublinhistoricmaps.ie/boundaries/connacht/


There are still some general boundary issues in the area.