For puzzle dependency charts, you might also like to try Puzzlon by @Adventuron author Chris Ainsley. It’s pretty easy to use once you get the hang of it. It requires minimal programming and formats the chart automatically. Ctrl+Space is all you need to let you know what you can do next.
For further info, see:
It’s all online, but you can copy your source code and paste into a text document to restore it later, or save the finished chart as an svg file to view in a browser.