I've been trying for days to add a second user to my account with the same domain.

It's becoming increasingly confusing to me, as it seems somehow the second user is only being used to send email from my username. This obviously makes no sense. All I want is for a second user with the same domain name to be able to access their own account on zoho and to be able to have those emails forwarded to their gmail account, as mine are. 

However, all my attempts to do this have been futile so far. It seems such a simple thing. I've been looking at all your help pages, but it's not clear to me what's going wrong.

Please help?