I'm working on a game that uses the excellent Yarn and YarnSpinner narrative toolkit for Unity. For this project, I'm also collaborating with a narrative designer -- unfortunately, the Yarn editor doesn't actually have a play mode or a testing mode built into it -- which makes it difficult to collaborate, because the designer can't even run through the Yarn scripts without downloading the entire Unity editor and project source! What if she just wants to test a short conversation script or two?
So, I basically duct-taped the YarnSpinner example setup to this excellent UnityStandaloneFileBrowser (for native file open dialogs at runtime) to make a very small simple tool to open and run through Yarn scripts. It can display your text, parse all your variables, and render up to 4 choices.
I call this tool "Yarn Weaver". The project source files are on GitHub under MIT License, or you can download Windows and Mac OSX release builds here. I hope it's useful for people!