Yes, there is a special rule ... But there is a en-passant which is even more special :-)

I knew DGT boards and if they could what I wanted, I would have propably bought one. They can capture pieces, but you can't show the move of the opponent on the board. I didn't want to put a distracting monitor besides my board ...

I knew this project, because I was curious about the surface you were using. Unfortunately - no offense - it was sooo loud and slow, that there was no way to use something like this for real chess games. But great video anyway :-)