Found the tune as taim_sinte_ar_do_thuama. I'll need to do some more digging for what may be multiple tunes. If I post here as ABC Notation do you have an ABC Player? If not may I suggest that you download ABCMUS from Henrik Norbeck in the meantime (for PC).

Regards, John

Here's my interim version without aligned lyrics:

X:1
T:taim_sinte_ar_do_thuama
M:3/4
L:1/8
Q:1/4=140
K:CMaj clef=treble
V:1 clef=TREBLE
V:1 clef=TREBLE
|"Am"z4 "C"D E|"C"G2 "Em"B2 "Am"A G|"C"G2 "C"G2 "C"G A|"C"c2 "C"e2 "C"d c|
"C"c B "C"c2 "C"c B|"Am"A2 "C"G2 "C"E2|"Am"A2 "C"G E "C"C D|"C"E2 "G"D2 "C"C2|
"C"C2 "C"C2 "C"E G|"Em"B2 "Am"A2 "C"G2|"C"G2 "C"G2 "C"G A|"C"c2 "C"e2 "C"d c|
"C"c2 "C"c2 "C"c B|"Am"A A "C"G2 "C"E2|"Am"A2 "C"G E "C"C D|"C"E2 "G"D2 "C"C2|
"C"C2 "C"C2|

and chords:

| Am C | / Em Am | C / / | / / / |
/ / / | Am C / | Am C / | / G C |
/ / / | Em Am C | / / / | / / / |
/ / / | Am C / | Am C / | / G C |
/ / |