I thought I got it sorted (sort of). To further clarify: on Mac B, only Tom is running Sync. In the event Jerry has worked on folder X, I have to switch to Tom to sync folder X with Mac A. As I see it now, this is the only way this can work. But I have noticed that in the event that Jerry creates a new file in folder X, this file will not sync. After I switched to Tom, Sync will show these files as locked. I'm sure that Jerry has closed the application (Word) before switching user. Both Tom & Jerry have admin privileges on Mac B.
Any thoughts? Thank a lot!