I am searching for a tool that will help in writing a game script. By "script" I mean the text core of a storyboard - without the drawing drafts, which may or may not be there (yet).

What I'm thinking of will let write a piece of text of the script, define a simplified workflow from that step, and then define the text of next steps, and so on.

Searching online, I found Inform http://inform7.com/ ("A Design System for Interactive Fiction Based on Natural Language") which in theory is exactly what I am searching for, but trying to use it it has this model of a space (a dungeon, a library) where you are picking up objects and exploring them. In my case I am designing more a Sims like game, the flow is entirely different.

Considering non specific software, mind mapping tools miss the linearity of the process. What I am writing is a directed graph - simply a work-flow, but the way I want to design it is more text based than work-flow based.

SO what I'm doing now is using a text editor, which I'll transform directly in code.

Any suggestions?