I've just found this site re Scottish repo research from the Scottish Executive. You might find it interesting 'http://www.scotland.gov.uk/library5/social/mars-15.asp'(posted 7744 days ago)It's dated 21st May 2001 and still states that the limitation period in Scotland is usually 5 years. If this hasn't changed the you must be pretty near the end of the limit, although you need to check what significance the extract decree has. There are some useful email & contact addresses too under there contact section. Looks like the CML applies to Scotland too as they've included it. Also see 'http://www.scotland.gov.uk/library5/social/mars-17.asp' for case studies. For the index see 'http://www.scotland.gov.uk/library5/social/mars-03.asp'.
Hope you find something useful.
Mark.