Welcome to A.Org. I also lurked for a long time before starting to post here (some may wish that I were still just a lurker).
Question: Why do you use a DKB SCSI controller card instead of the SCSI controller on the GVP TekMagic accelerator? I have just revived my A2000 with the TekMagic 060/50mHz, but I am having trouble getting OS3.9 to access my CDROM. I am searching for my AsimCDFS 3.9 disk to re-install. Using the TekMagic SCSI tools, I can see the CDROM, just can't get any access to it from the OS.