Dear Bruce. The information in your posting and others is very interesting to me as I am researching Comack in Banbridge, County Down.So far I have Hugh Cammock b. 1864 parents William Cammock and Mary Carr. also his sister Susanna Commack b. 1866 parents William Commack and Mary Kerr. I believe Hugh is my great grandfather.You are correct that there are many spellings.In LDS I got best results by using Cammack and Comack.Under Cammack there are 6 listings for Alexander.Don't know if there is a connection.Good Luck. Heather.