With my apologies, I need to correct something I said about Wemyss. It's in Angus, not Fife, and is 45 miles from Dunning, not 35. However, there's this adult Andrew Christie in Fifeshire in 1813...
On 19 March 1813, an indenture was registered in the Burgh of Inverkeithing between William Walker and John Crawford and Andrew Christie and his cautioner. Inverkeithing is definitely in Fifeshire, about 29 miles SE of Dunning. I found the document extract at the website of National Records of Scotland. Also ...
In Crieff, Perthshire, Andrew Christie was an ironmonger and/or grocer during the years 1844-1849, In 1844, he was partners with a William McEwen.
The above is found in Reference Nos. B34/15/7, CS280/30/80, CS280/11/13, CS280/35/27/2 at
http://catalogue.nrscotland.gov.uk/nrsonlinecatalogue/search.aspx.
Finally, I assume you've also looked for the spelling Chrystie.