I have the exact same problem. Resurrected a K5 from the dead and am now trying to load patches thru midi but it hates sysex. Tried several programs and it just ignores the request syn/ack completely. I am thinking about snagging a 1.3 rom as mine is 1.0 like yours. Very frustrated to put in 20 hours of restoring this beast and not able to do much. Let me know if you have a breakthru or if the rom works for you and good luck :)