Hi,
Can't help you directly, sorry. But I just wanted to metion something that was of interest to me, as I have crofters in my line too (from the Highlands, near Ft William). I visited Skye last year and picked up a very interesting book by David Craig called On the Crofter's Trail.
http://www.amazon.co.uk/Crofters-Trail-Craig-David/dp/184158455XIt's largely about the Highland Clearances and covers many areas, including Canada. But it gives a wonderful oral history of the crofting tradition from descendents of the crofters left behind in many areas, including on Skye. And it's very moving in places. It's a while since I read it, and my uncle has borrowed it now so I can't check, but I can't recall seeing Anderson's named specifically, but sevaral family names are mentioned, so you may spot one.
There are many old croft buildings littering the Skye landscape and, if you haven't been there yet, I'd recommend a visit before they disappear. The Museum of Island Life is of particular interest, as it is actually located on an old croft.
http://www.skyemuseum.co.uk/Also, it's my understanding that crofters, as they lived on the edge of the land, and eeked out a living however they could, were also considered fishermen. So I wouldn't discount finding Roderick as a crofter too.
Regards, Ann