Mattzobricks has published building instructions for the MLC mega. MLC stand for MattzoLayoutController, a device to control any land-based components of a LEGO train layout.
The MLC mega is able to control 16 switches or form signals, 8 light signals, and 16 sensors. For many users, the powerful MLC mega will be the one device that fulfils all needs to automate their train layouts.
The MLC mega integrates some PCBs that were designed especially for this controller. They are contained in the instructions package, and can be used to easily order the parts from PCB producers.
The instruction package also contains the STL files needed to print the case with a 3D printer.
All information including the instructions can be found on this page. The instructions are presently in German only, but will likely be translated into English in the future. We plan to release a video on Youtube in the future as well.