Creag Ghuanach isn't only a TUNE to which The Mingulay Boat Song by Hugh Robertson, and later An Cailín Álainn by Tomás MacEoin, were set. It is also the title of an older song (words dating back to the 16th century). The lyrics were already on Mudcat, and I've added more verses and a translation of three of the verses to the discussion at
https://mudcat.org/thread.cfm?threadid=10414   "Mingulay Boat Song again"

And lyrics Màirí Bhan, the inspiration for the Lewis Bridal Song aka Màirí's wedding, referred to in the Wikipedia article (previous post) are also already on Mudcat. I've added the translation by Anne Lorne Gillies to the thread where those lyrics are posted Origins: Mairi's Wedding