Actually the api is pretty straight forward. You should be able to do everything using the Ajax plug and Kyat's Cb hash
Obviously it would be somewhat awkward to make an example as you would have to expose the private key in the capx.
I would suggest some experimentation. Set up a game on the site, gather the required info, and test away.
If you have any questions they have a chat on GameJolt, and there's always the forum here.