Sorry, I do not how to post a file on the internet. (Anyway my scenarios are quite rough and ready, I spend about 5 minutes preparing one then play it and create a new scenario next game)
You can set civilisations so they can build settlers. Go into the editor and select the "units" tab, then select settler and unmark any civilisation you want to prevent from building settlers.
To change civilisation traits, select the "civilisations" tab, the select a civilisation and check whatever traits you want and you can do the same with techs.
To give an extra settler or other starting units to a civilisation use the Player Data option.
Hope this helps.