This project is built using the build system developed by the humble bundle developers for a sample game .
In fact, you can think of this project as a template for a CEGUI-based game targetting the humble store / humble widget.
For help building / an introduction to emscripten I recommend to read that blog post . Also, I put detailed notes in the README.md in the root of repository.
Caveat Emptor: My GLES2 port is not really finished, some functions I simply commented out and replaced with
assert(false && "Not implemented yet!");