Farm Naming/Locations

1. In general, I am trying to understand the farm naming, specifically øvre, nedre and u. I sometimes cannot find the names in Oluf Rygh, and I get thoroughly confused on how to record the locations. I do understand that many, if not all, are huusmandsplads and may not be in Rygh. 2. Specifically, I am currently looking at Rønningen u Verpe, which I believe is in Bø i Telemark, and Moen u Myrene, either in Bø or Seljord. 3. I have a person who was born at Rønningen, which is shown in both his baptism record (as Rønningen) and his burial record (as u Verpe), but his baptismal record is found in Seljord, not Bø. The year is 1822. My question ... why would they record in a different parish than they lived? Any clarifications or explanations on naming, etc. would be much appreciated.