Okay, two things here. First, check with Fostex--they can be slow to return e-mail, but they will, eventually.
Second, while you wait for Fostex, and this is just a guess. You mentioned that this started when you connected the SCSI 250mb Zip. You are implying that you either used the SCSI 100mb Zip, an internal hard drive, or the wrong Zip. I'm guessing you used the 100mb Zip prior. If so, are you reading info fro 100mb discs? Does the Zip drive need to be told it is using a 100mb disc rather thana 250mb. I don't use the Zip disc--I use the Orb drive--so I honestly don't have a clue. It's just a guess. I wish more manuals would give you a detailed list of error messages--it would certainly make life easier.
Peace, Jim