Stan, it doesn't look as if abc2ly is maintained and it may be dropped.

I've tried a more roundabout route: abc2musicxml then musicxml2ly here:

\version "2.18.2"
  % automatically converted by musicxml2ly from kesh.xml
  
  \header {
      source = "John B. Walsh Session Tunes"
      encoder = "abc2xml version 84"
      encodingdate = "2018-06-19"
      title = "The Kesh Jig"
      }
  
  \layout {
      \context { \Score
          autoBeaming = ##f
          }
      }
  PartPOneVoiceOne =  \relative d' {
      \key g \major \time 6/8 | % 1
      \mark \markup { \box { A } } \repeat volta 2 {
          d8 s8*5 | % 2
          g4. g8 [ a8 b8 ] | % 3
          a8 [ b8 a8 ] a8 [ b8 d8 ] | % 4
          e8 [ d8 d8 ] g8 [ d8 d8 ] | % 5
          e8 [ d8 b8 ] d8 [ b8 a8 ] | % 6
          g4. g8 [ a8 b8 ] | % 7
          a8 [ b8 a8 ] a8 [ b8 d8 ] | % 8
          e8 [ d8 d8 ] g8 [ d8 b8 ] | % 9
          a8 [ g8 fis8 ] g4 }
      s8 | \barNumberCheck #10
      \mark \markup { \box { B } } \repeat volta 2 {
          | \barNumberCheck #10
          a8 s8*5 | % 11
          b4. d8 [ b8 d8 ] | % 12
          e8 [ g8 e8 ] d8 [ b8 g8 ] | % 13
          b4. d8 [ b8 g8 ] | % 14
          a8 [ b8 a8 ] a8 [ g8 a8 ] | % 15
          b8 [ a8 b8 ] d8 [ b8 d8 ] | % 16
          e8 [ g8 e8 ] d8 [ b8 d8 ] | % 17
          g8 [ fis8 g8 ] a8 [ g8 a8 ] | % 18
          b8 [ g8 fis8 ] g4 }
      }
  
  PartPOneVoiceOneChords =  \chordmode {
      \repeat volta 2 {
          \repeat volta 2 {
              | % 1
              s2. | % 2
              g4.:5 s8 s8 s8 | % 3
              d8:5 s8 s8 s8 s8 s8 | % 4
              g8:5 s8 s8 s8 s8 s8 | % 5
              g8:5 s8 s8 d8:5 s8 s8 | % 6
              g4.:5 s8 s8 s8 | % 7
              d8:5 s8 s8 s8 s8 s8 | % 8
              g8:5 s8 s8 s8 s8 s8 | % 9
              d8:5 s8 s8 g4:5 }
          s8 | \barNumberCheck #10
          s2. | % 11
          g4.:5 s8 s8 s8 | % 12
          c8:5 s8 s8 g8:5 s8 s8 | % 13
          g4.:5 s8 s8 s8 | % 14
          d8:5 s8 s8 s8 s8 s8 | % 15
          g8:5 s8 s8 s8 s8 s8 | % 16
          c8:5 s8 s8 g8:5 s8 s8 | % 17
          g8:5 s8 s8 d8:5 s8 s8 | % 18
          g8:5 s8 s8 s4 }
      }
  
  
  % The score definition
  \score {
      <<
          \context ChordNames = "PartPOneVoiceOneChords" \PartPOneVoiceOneChords
          \new Staff <<
              \context Staff << 
                  \context Voice = "PartPOneVoiceOne" { \PartPOneVoiceOne }
                  >>
              >>
          
          >>
      \layout {}
      % To create MIDI output, uncomment the following line:
      %  \midi {}
      }
  

It looks a bit different but...