Q1. Did you login from multiple places at the same time? A1. No, my collaborator and I are in different time zones altogether.
Q2. Did you paste anything into an Arrangement? A2. No, and as I've said earlier, nothing happened before it got corrupted.
Q3: What exactly happens? A3: I can't enter Screen3 at all; it only notifies me that there's an error. I'm not able to view the screen at all. None of the panes open.