Normally I'll key on engine off and observe for a rock steady SES light on. If it's flashing rapidly as you say, this indicates no communication with the PROM. I'd double check your solder connections. You make no mention of which 5 pins you added the jumper to. There's no mention of how you burned the bin onto the PROM. One can only assume you stacked the bin or used offsets. Are you able to remove the stock PROM from the carrier and drop it onto your zif with the same results?