+1 i really think lot of people who are interested by the emulators, are interested in recover the sensation from the arcade at home. So if possible, it will be awesome one day that demul can perform the ffb. Because the racing games library proposed by demul deserve that someone devote onself to it.
I personally own a dfgt (logitech) and really hope one day , someone add the ffb to this excellent emulator.

I think too that you need help to work on this project. I can't help u infortunatelly. But could you tell me what is the coding language for demul? His it ''C language" thanks.