I hope you mean MacroDroid and not the forum. Cause I can't find that in MC.If you go into account details next to your username you should see a button saying "Change".
However you must wait 30 days after creating your account and each time you change your username.
That's the thing. I am talking about MC itself.I did mean the forum.
Already mailed you. Thanks oncr again.Sorry but I don't support changing of usernames in MacroDroid. The simplest way would be to make a new account with a different email address.