Hello. I'm Nick.
Amir graciously gifted me a copy of DragonRuby a few weeks ago, and after the new version came out yesterday I decided it was time to dig in.
I don't really understand the programming style in the tutorials, so I decided to piece together what I could from some of the samples to make a more Ruby-like tutorial. I wanted to show off a few Ruby features, and I documented the code with the assumption that it's an introduction to some Ruby concepts.
https://github.com/kniknoo/oo_dragon_demo
This demo just shows off the dragon with U/D/L/R control, including vflip, as well as defining and extending an object class. The Castle came from a stock image provider.
Hope y'all find this helpful, and I can't wait to see other people's projects!