@Phantom
nobodyii's suggesting to link the onboard SCSI header with the header on the backplate SCSI module to take advantage of the bus termination the module provides.
(good call there's the 'ii' at the end of his alias or that sentence would read really weird

).
That way if the SCSI chip and/or firmware expects to see a terminated bus, it will.
I have a suitable cable here to provide termination directly (without connecting to the SCSI module) as a 2nd way of testing nobodyii's suggestion.
EDIT: Then I will kick your @$$ in Kick Off 2. Or the other way round
As for the -0.5 MB RAM, the same happens with my CS PPC too, f/w 44.67, no MapROM or anything peculiar in the early menu settings.
So I see three possibilities:
1. OS 3.9 rekicking. But it doesn't happen with my A1200 + Blizzard 1230 IV, full 128 meg shows there. Unlikely, therefore.
2. CS PPC "internal use". The CS PPC reserves for itself a 512 KB block of RAM for whatever use. This seems strange though as the same RAM could be reserved, if needed, in an OS-specific method. Unlikely, therefore.
3. 68040/68060 libraries. So, I checked my Blizzard 1260 + 3.1 OS installation and 0.5 MB is missing there too.
So I suppose the 0.5 MB is "lost" when the 68060 library is initialised.