As for booting milo.bios.dd, you say that you see the floppy light go
on for a while and then go off. That sounds like the SROM is reading
the failsafe boot block floppy (for that is what it is) and then
starting to execute it but that the video is not getting inititalised
for whatever reason.
I would hook up serial port 1 (if you can) at 9600 baud with no stop
bits, no xon/xoff and 8 data bits. Using either boot option, you should
see something meaningful echoed to the serial port. If you cannot do this,
then can you borrow a bog standard ISA VGA card and try that in the box along
with the
milo.dd (the non-bios bog standard isa vga version of milo?
Dave