I have been testing PLAYER ROLE ASSIGNMENT in the Dialog Editor and it appears that assignment of roles based on skills does not function: things like Stealth, Acrobatics, Investigation, etcetera. You can even simply try a single role - assign to the person best at "Diplomacy" - and it will not assign a character to the dialog role. If all of the roles you attempt to assign are based on skills, you get a situation where no character gets assigned to any role, and the dialogue stalls.
I have tested and assigning roles works just fine for the races, classes, and backgrounds - but not skills. (I did not test the worshipped gods).
I have no mods. I am using version: "1.4.33 - public". The only DLC I have is the Sorcerer update.
This would be a very useful function to have operating, as it would allow you to assign the best character to the proper skill check during dialogues.