Basic problem: If a page number doesn't exist in a resource, you're taken to another resource in the same series where the page number does exist.
Expected behaviour: To be taken to the nearest page number in the current resource.
To repeat: Open the NICNT commentary on 1 Corinthians. Type pg 24 in the resource location box. You'll end up in Mark's gospel. Go back to Corinthians and type pg 25 or pg 26. This time you'll end up in Matthew's gospel.
