Looks like a board I would replace. Problem is definitely because of the acid damage which migrated to the back side of the board.
If you don't like Rottendog, PinLED also has a replacement.
http://shop.pinled.de/product_info.php?cPath=1_11&products_id=184

Original boards in nice working shape are very hard to come by.

No big deal having some extra connectors not being used. Though, at first you had some garbled display so that still is suggesting you have bad connection on the ribbon cable. You could swap the cabile and/or DMD with Getaway to verify which is still giving you the current issue.

Scratch my last post.

Oh I do believe that the original ribbon cable is wrapped through/around a ferrite. I think this actaually is to reduce the extra dots/distortion you are seeing. I would actually swap back to that cable. If the DMD is garbled again, reseat both sides of the cable.