Oooops, my bad, I just had to enable SCSI support in kernel menuconfig, it works as expected now. With no naming rules the drive is presented as /dev/sr0, not surprisingly.
I still get the warning at system console:
"configuration error - unknown item 'MD_CRYPT_ENAB' (notify administrator)". This is seen when a login attempt is made, right after username is entered, before the password prompt is presented.
Golly, I wonder if this is another menuconfig issue. Anyway, we live and we learn, and another one bites the dust.