this is my diy led build i now want to make a microcontroller to do the same as your wanting but only new to this and have a lot to learn yet but like this link u have found have a look at my led buid http://www.thereefuge.com/threads/my-diy-led-build.229/
Looking at that Typhon controller and what you want to do with it, Cornelius, I'm wondering why you want to use that controller. Since you're going to be re-writing it I don't see much advantage in using it; you could get the same functionality with a regular Arduino controller and a display shield -- or just get a separate display and a few switches and build your interface (would make for a simpler enclosure...).I assume that due to the display and switches that the Typhon is cramped to just 4 PWM outputs for LED drivers. A typical Uno-compatible will have 6 PWM outputs or you could get a Mega with 14 (and save money by only needing one board).
If it's possible it's not going to be at all simple. The controllers you have appear to have almost all of their inputs already in use, and simply mating with the available ethernet boards would require soldering wires to the controllers.