It turns out I spoke a slight untruth- it wasn't an "ALPHA"
config file, it was something that started as that, but
then became different. I've built and booted a GENERIC
and things are happy. I'm now working backwards to figure
out what it was that caused this sadness to occur.

Would it be possible that *these* options are not good?

options         MAXPHYS=0x100000
options         MAXBSIZE=0x040000