I do not pretend to understand DNA, so am not much help when asked to explain links.
However, changes at Yahoo have led to the content of the Douglas DNA forums moving to the Douglas Archives, so you may find something of interest…"
"Finding Mortons. My Grandmother Laura J (Hall) Olson had Morton cousins, and I even met her cousin "Uncle" Clyde Morton. This was all in Michigan many years ago. Their Morton family came from Loudoun, Ayrshire, Scotland thru Alexander…"
Which Douglas line are you researching? Dates and places help making connections.
The connection of the Morton line to my family ancestors, starting with our Adam Morton, Loudoun, Ayreshire, Scotland. And the connection of the Mortons to Mary, Queen of Scots. And if James Douglas, 4th Earl of Morton was related to Elizabeth I of England.
The more information you can give about the people you mention, the more chance there is of someone else connecting with your family.
Dates and places of births, deaths and marriages all help to place families.
Professions also help.
'My great-grandmother mother was a Douglas from Montrose' does not give many clues to follow up! But a bit of flesh on the bones makes further research possible. But if we are told who she married, what his profession was and where the children were baptised, then we can get to work.
Maybe it is time to update the information in your profile?