I have added a new feature in Pinball-Browser : the ability to display the scores in a PC window (and maybe additional infos in the future). It just requires an USB adapter to connect to the Sam board and a patch in the firmware.
There is a slight delay between the dmd and the screen on the pc, but I'm working on it.
I also have some work to do to make it game independant (it only works on AC/DC for now); A new Pinball-Browser version will be published when it's ready.
Based on this, a small dmd could be used on the apron (and connected to a Rapberry instead of a PC).
(for those who don't know about Pinball-Browser, see this thread : http://pinside.com/pinball/forum/topic/acdc-display-and-modify-dot-matrix-images)