Today saw the majority assembly and partial testing of the Dual Motor Driver add-on board. It is not as high-quality or complete of an assembly job as I usually do as I had to make use of my personal soldering equipment (which is nowhere near as nice as what I have access to at my college). Despite those difficulties, I was able to assemble enough of the board for it to be fully functional and to find a couple (very minor) things I'd like to change to simplify the assembly process.
So far I have only tested motor driving with it, and it's worked beautifully. I was able to drive the TiltyWay motors without any problems at all almost as soon as I had it assembled and programmed. I'm hoping to test the encoder sensing tomorrow, which I'm honestly not sure will work. The motors are so fast and have such high resolution encoders, that the Atmega328 microcontroller on the add-on board might not be able to keep up. But that is what testing is for, and if it doesn't work, I'll find a way to fix it!
Today also saw the (partial) completion of the Tilty Omni. The circuit board has all of the features designed and laid out, and now only awaits final review and labeling tomorrow before I order the first prototype.