text: What I meant above was that the whole civil parish of balla is missing.
  
  The colour of both parishes from the Memorial Atlas source were very similar so that Might be why it was missed. I can go ahead and try to add the missing parish of Balla but ...
  
  Doing this would split a separated part of the "mayo" civil parish (named "Mayo (clanmorris portion)" in OSM ..for now) apart from the rest of the mayo parish. This townland "Brownhall Demense" seems to be part of the "Mayo" civil parish. One the map it says "Mayo (pt of)" under the townland name.