No I unfortunately am not an electronic engineer. Just a musician. :-)
I looked at that link and it looks to me that it is mainly designed for a locomotive controller. I cold be wrong. Were you using it as a blueprint for a MIDI controller?
If you're not a little of an electronicien, give up. If you aim to do your own to save some money, I'll say it clear: you won't save any buck. You need too much skill and equipment to do it yourself.
Of course, if you got an electro-dude among your friends, he'll certainly take up the challenge.