This is what I hear Isla St Clair singing. Warning: there may be mondegreens present ;-)

MACCRIMMON'S LAMENT (Isla St Clair on her album Inheritance)

A misty road unfolds round Coolin
A dirge of woe the banshee is croonin
But my blue e'en they wail and seething
Since thou art gone and no returning.

The breeze o'er the ben is gently stealing
As doon their braes the burnlets come creeping
Birds in high trees they wail and seething
Since thou art gone and no restoring.

O'er the doon at e'en your piping is silent
Nor echoing hills in like replying
My lover's fond kiss is fondly quieted
Since thou art gone, for I, for ever.

Cha till, cha till, cha till MacCrimmon
In peace nor in war return no never
No treasure nor road shall bring MacCrimmon
Till dawns the glad day that joins us ever.

Glossary (from the album's liner notes): banshee: death spirit; e'en: eyes; ben: hill; doon: down; braes: slopes; burnlets: small streams

According to Hamish Henderson's sleeve notes on her 1971 album Isla St Clair Sings Traditional Scottish Songs, this translation from the Gaelic was made in 1966 by Geordie Macdonald, a native Gaelic speaker from Lewis.