Sounds like their might be a case that is still not covered. If you would be willing to provide more details on your user's repro steps it would be great if you could contact me directly (bbaffy@perforce).
I've sent you a PM. Hoping to discuss this directly to determine what the bug is. From the log you posted, it seems that your workspace root is being identified as somewhere different from both the workspace root you mentioned and the mapped drive (D:\product_v1).