If i was you I would be getting onto Aplejohn.
From what I can see of the video, he/she likes to show how things work but are a bit short handed when it comes to publishing any proper documentation on how anyone else can do it.
Okay you have some code and PCB layouts and circuit, but if they don't tell you how to load what software, its a bit of a loss if you don't know where to start.
Pity because of the amount of effort and coding that must have gone into the project.
Just to have his/her smarty phone controlled from the steering wheel buttons.