change custom username in application prefs

[Miko]

i am trying to write a script that will let me change the custom username in application preferences. i have written a script with a custom dialog that allows the user to chose a new username and then copies it to the clipboard. i need the applescript to pick it up from there and paste it within the application preferences window.

what i can't seem to locate is the way to access items that are under the filemaker pro menu in os x which is where these preferences are. i opened the dictionary and see how to get to all but this menu.

anyone know how this would get scripted?

thanks,

Limore