Does becoming a vassal work properly?

I think I read somewhere that becoming a vassal was buggy. If so, how buggy is it?

No (maybe with the "legion" nobles)

When I modded SoD I forgot to make certain functions available to the player if he was a vassal instead of a King. It is playable but don't be a King first then a vassal after.

In the new version gameplay will change based on your current occupation. So hopefully I can provide some new roles as long as they have some form of management.