I noticed when switching from ESDI to SCSI on the PS2 M70(486) that the SCSI disk IDs are backwards compared to their drive letter representation in the UI. Reading online it seems ID 6 should be the boot disk, and the IDs should count down from there. (This also ignores that the drive letters in the UI are wrong if you partition the disks into smaller chunks but I digress)
I also noticed that I can't put a CDROM in ID 0 (the reference disk sees it, but DOS doesn't), but it will work if I put it in ID 3 (websites online recommend putting it in the lowest slot, but I've also seen recommendations to put it in slot 3 or lower).
More of a graphical bug than anything, but thought I should mention it. Thanks again for your work on this amazing software.