I just reviewed the 1841 census again and the nailor certainly isn't the right entry. Here's the one that I think has possibilities:

1841 census at Dollough Beg, Ballaugh HO107/1463/4 2 19 pg 10 (464355)
Thomas CRAINE 73 [no occupation listed] Y
Mary Ann CRAINE 35 Y [matches 1800 child of Thomas Crane & Mary Cowel]
Jane CRAINE 30 Y [matches 1803 child of Thos & Mary]
Margaret CRAINE 14 Y [matches eldest child of Thos Craine & Elizabeth Gelling]
John CRAINE 11 Y [matches 3rd child of Thos Craine & Elizabeth Gelling]

[immediately above also at Dollough Beg are:]
John CRAINE 84 Farmer Y
Ann CRAINE 77 Y
Margaret CRAINE 50 Y
John CRAINE 45 Farmer Y
Jametta [?] CRAINE 5 Y [age marked in female column]
>Mary Ann CAINE 15 Female Servant

[immediately above this at Dollough Maor are:]
James CRAINE 60 Y
Isabella CRAINE 50 Y
Thos CRAINE 15 Y
Elizabeth Jane CRAINE 13 Y