Cyan Worlds, Inc. has put most of the program code sources for Myst Online: Uru Live into open source. This includes the code for the client, tools and python scripts. With these sources you can find out how MOUL ticks. And with the MOSS server, fans can set up and run Myst Online: Uru Live on their own servers, in addition to the Cyan Worlds Myst Online: Uru Live servers.
The 3D models and textures that were used to create Myst Online: Uru Live will not be part of the open source license. We will probably release some of these models and textures, but under a different license than the code source.
The grand hope is that you fan developers will create fixes, improvements, new Ages and new game play, that will keep Uru alive. Thanks!
There are (at least) two places where you can view, get, collaborate and explore the released open sources and it's branches:
The Myst Online: Uru Live Open Source Team