I've created a QuestKit ScratchPad, which lets you play around creating QuestKit files and running them, without having to download anything.http://docs.textadventures.co.uk/questkit/scratchpad/
I'll flesh this out with more features soon, like the ability to load a QuestKit script from a GitHub gist, or some other external file. I think it would be cool for all the live examples to have an "open in ScratchPad" link so you could play around with them.
You could use this to try out QuestKit before installing it, and I think it will also be good when people are looking for help and examples on the forums.
The ScratchPad is automatically deployed every time a checkin is made to the QuestKit code on GitHub, so it will always be running the very latest version.