Yeah, I have no idea what is going on there. I am not aware of any expansions for the front memory expansion to take it over 512kb. I haven't taken a good look inside it since that screenshot though, so I'm guessing there is something in there to explain for the extra memory.
There were a couple front memory expansions that added 512K.. but in this case, You can see the wires from the piggybacked expansion done on the motherboard in the pics (under the daughter board)
