Hi guys, well it took a little while to get back to solving this mystery, but I'm glad to report a happy ending.
I went ahead and manually re-flashed the eprom on the board, without removing the device (with a clip).
I simply could not get it to flash via the serial port at all, no matter what I tried, used the CH341 programmer, with the most recent abs file from the Ferguson site.
It took some finagling to get it to work though, I had to do several erase steps with different programming sw, before the device would program error free.
The most sucessful software I found to work was 'AsProgrammer' - worked the best for me.
Thanks for all your help and responses up to now!
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