Hi Thomas; this probably will not break down the wall but I noticed that the marriage was registered (1811) at the Parish Church at Drumblade in Aberdeenshire. (
https://familysearch.org/ark:/61903/1:1:XTNF-25N) Lessendrum is also at Drumblade. Lessendrum was the hereditary estates of the Bissets. I also notice the four children were christened there: Jean Forrester (b. 1815, c. 1818), Jannet Mary (b. 1816, c. 1818, at the same time as her sister), Andrew Leith Hay Cumming (b. 1818, c. 1821) and John Robert Aberdeen Cumming (b. 1820, c. 1821 at the same time as his brother). Given the names of the children and the location of the marriage and christening I would certainly search in the vicinity of Drumblade. There are a few pages of material on Scottish people; there is a certification by James Coull (?), Rector of the Parishes of St. Peter and St. George "in the island of Antigua" that he married the couple. Nothing I found about his parents though. Drumblade church was only built 1773 by the look, although may have been one prior, and records were notoriously incomplete before 1780/90.