"Actually, Allan, not so simple, but thanks for responding."

Ay fair dos - maybe I'm not taking enough account of non-Scots having the unfamilar words/spelling to deal with. It is pretty straight forward though if you really look at it. The text isn't really that obscure. The repeating theme throughout the song is that the person can't sleep at night because of thinking about a lover. They are always awake!

"Aye waukin' O,
Waukin' aye and weary,
Sleep I can get nane,
For thinkin' o' my dearie."

translates basically as

"Always awake O,
Awake always and weary
Sleep I can get none
For thinking of my dearie"

Apart from the spelling of "waukin" and "nane" which are close enough to the English to make an educated guess anyway the only unfamiliar thing may be the Scots word "aye" which means "always".