Hi Frances,
1- You use your GDI username.
2 - With GDI Coop it really depends on how, or if, you personally market the page they give you. On average you will mostly be getting people already in GDI and you can earn a little money from the commissions generated when they pay their membership dues.
You can get GDI sign-ups if you let them do the advertising for you, but like any team page these are few and far between. I wanted to test them so I became a member for 6 months. (To me 6 months is the minimum to testing anything online.) I did not advertise the page they gave me, and just bought into the rotate option. In that 6 months I had one GDI sign-up and about 10 people who were already in GDI sign up under me.
Not saying it's good or bad, that is just my personal experience. And again, I did not spend any time at all advertising the page they gave me. It was all through their autopilot program and meant only to see if their results were the same as many of the other "teams" out there.
Vincent Parker