Dear rvw: As I have discovered, there are very few "definitive" versions of any folk song. And for this one in particular they vary all over the map, usually with some complicated time signature changes. Since this song tends towards free-form, a performer can easily improvise as needed. Anyway, within the bounds of a constant time signature, treble for a voice-like instrument, and minimalist base line suitable for a folk song, this is the result. Using a music editor (not equal tempered piano), verifying a correct chord from among several possibilities and inversions is straight forward. But chords can sound dramatically different depending on instrumentation, which music theory doesn't address. Hope this helps.
take music theory