Tengu Gamelib is now on Github.
https://github.com/DaVince/Tengu-GameLib

There is also a new release.
Gamelib (v0.4) (2011-08-15)

Change log:

• The canvas is now created inside the script itself (canvas resolution can be passed to Gamelib.init()).
• Moved all functions and variables into the Gamelib “namespace” (just an object holding it all).
• Renamed Main() to Gamelib.init().
• Added Gamelib.State.onstart() which runs only once: when starting the state.
• A state’s update method is no longer mandatory (but not recommended).
• Added testing/template page.
• Moved debug panel to a (hopefully) more convenient spot.

This is the engine I’ve been using and working on to create the game World Of Creation. It’s a homebrewn little solution, probably not 100% efficient, but it works, and it easily lets you manage and switch between game states (as well as providing a few features to quickly make a game). It is licensed under the new BSD license.

GameLib (v0.3) (2011-04-24)

Documentation is included, see the readme.

Demos
In-progress game using the engine
Older engine test (using v0.1)