Not sure if I'm right about this but I have just started to do it this way:
I use the name type. Add a new name and click the blue info item at the right hand end then enter the Type as required.
So AKA for somebody who uses an alternate name, apparently deliberately. Eg one of my people was Maria Cady but, for much of her younger time she used her stepfather's surname so she went by Maria Mitchell.
You can use Maiden, Professional name, etc so Archie Leach might be entered as Cary Grant with the name type of PROFESSIONAL.
You can also just add the text to the GEDCOM in form
1 NAME Cary Grant
2 TYPE PROFESSIONAL
You can also add types to the Menu by editing the Default (or other) Style in the right spot but I forget where I did that.
I added ALTSPELLING for those cases where the name is spelled differently in say, a baptism record, or whatever but it's obviously not an AKA.
If I'm committing a heinous mistake here, please somebody point it out.
Cheers
Mick