This project is abandoned and its default file will likely not work with the most recent version of World of Warcraft. Whether this project is out of date or its author has marked it as abandoned, this project is no longer maintained.
libwaterfall 1.0.3.01 keeps causing wow to crash (critical error) if it is selected to load on login. If it is unmarked, and is loaded afterwards by an addon, it will work.
Parnic, a developer of IceHUD, sayed that perhaps its some problem in Waterfall library that he used for IceHUD.
Here foto of the bug. http://pic.ipicture.ru/uploads/090816/Ja2ZI9DBhF.jpg