Thanks, it is now working. all the documentation i found on this is sort of misleading.
in the nx-148 manual:
"11 CUSTOM MSG. LOCK? Enable Custom Message Lock. Prevents over-writing the custom message
during keypad copy."
this doesn't seem to really be how it functions.
the nx-10 manual says:
"Custom Message Lock A menu option that makes the customized keypad
message on the programmed keypad independent from
other keypads in the system. If disabled, editing the
custom message on any keypad affects all keypads in the system, i.e. all keypads always display the same message. "
which is also not really how it was working.
both keypads had "custom message" enabled and custom message lock disabled, and both showed different messages after I edited devices>keypad text.
but now its working so thats really all that matters

I was also going crazy with a ground fault on zone 8 where i have fire alarms when i knew it was ok since it was working with the old board.
after playing around for a while I saw the option for "enable 2 wire smokes", in the dlx-900 help it says this is only for the nx-8e but it is working and what was needed.