It might not be a walkthrough in the more typical sense of the word, but if you download the game and go to the "more options" section there's a menu item for scene flowcharts that will give you a good idea of how each option affects the outcome of the scene. They're a little harder to read in the web version though since I had to reduce the size of all the images so I could fit the whole game on the site here. At some point I should probably write up an actual walkthrough though