I spotted the typo and have use support@matrixorbital.com
and
support@matrix-orbital.com
and they all have bounced

I got the same ?????

have there been any developments with the replacement LK204-25PC's yet

I emailed MO a week ago and have still had no response, I have also sent Henry a private message and had no reply.
A strange silence has descended. I think MO should try and be bit more honest before they get a bad name.
Especially as their products are generally excellent.

I'm no expert, but i can't see a problem.
Your LCD will stop receiving a signal from the serial port when you turn off your no.1 PSU. So the LCD will go to the startup screen stored in it's ROM.
The only danger is if your forget to turn off the second PSU, you could burn your screen out quicker by ...

I've just spent two days wiring up a keypad and GPO's 3-8.
Only to find that 6,7 and 8 all come on when i press any key on my keypad.

Is there a fix for this problem?

Also it would have been nice if it was mentioned on the MO website, as I could have saved myself a considerable amount of time ...