Adding people not in my tree

LA Fernandes

How can I add someone to my FT Group, if they are not in my tree?

1- Sometimes I collaborate with other people´s trees and it would be helpful if I could be in the group, although I´m not in their family tree.

2 - I have a member´s account and a non-member account, which I use to teach people how to use FT, but I´m not able to invite my non-member username to join my FT Group. If I could it would be easier to fill up that tree.